U.S. trading partners offered a cautious welcome to the U.S. Supreme Court’s decision Friday to strike down large parts of President Donald Trump’s flagship trade policy on global tariffs — but global trade bodies warned of lingering uncertainty surrounding import levies.

The law that undergirds the import duties “does not authorize the President to impose tariffs,” the majority ruled six to three in the long-awaited Supreme Court decision.

Hours after the ruling, Trump said he signed an executive order imposing a new 10% “global tariff”. The “Section 122” tariffs will take effect “almost immediately,” Trump said. At a White House press briefing Friday afternoon, Trump railed against the “deeply disappointing” 6-3 ruling.

Trump’s tariff regime impacted a swathe of countries from the U.K. to India and the European Union. Some governments, like Vietnam and Brazil are still in negotiations.

Taiwan, home to the the world’s leading contract chipmaker and producer of the most advanced semiconductors, said the 10% flat tariff rate would, according to an initial assessment, have a “limited impact” on its economy.

The island will continue to “closely monitor” developments and maintain close communication with the U.S. to understand the specific measures and respond in a timely manner, the Taiwanese cabinet said in a statement on Saturday.

French President Emmanuel Macron reportedly said the Supreme Court’s ruling proved the benefit of having an effective counterweight to power.

“It is not bad to have a Supreme Court and, therefore, the rule of law,” Reuters quoted him as saying at an event in Paris on Saturday.

A U.K. government spokesperson said the country would continue to work with the White House administration to understand how the ruling will affect tariffs for the U.K. and the rest of the world

“This is a matter for the U.S. to determine but we will continue to support U.K. businesses as further details are announced,” the spokesperson said.

“The U.K. enjoys the lowest reciprocal tariffs globally, and under any scenario we expect our privileged trading position with the U.S. to continue.” The U.K. agreed a wide-ranging trade deal with the U.S. in May last year, which imposed a broad 10% levy on many goods, but also included certain carve-outs on steel, aluminum, cars and pharmaceuticals.

The Supreme Court case focused mainly on reciprocal tariffs, and the ruling leaves much of the U.K.’s trade deal with the U.S. — including preferential sectoral tariffs on steel, pharmaceuticals and autos — unaffected.

However, the British Chambers of Commerce (BCC) trade body said the U.S. Supreme Court decision adds to the ongoing uncertainty around levies.

William Bain, head of trade policy at the BCC, said the move “does little to clear the murky waters” for British businesses, warning that the President still has “other options at his disposal” to retain his current regime on steel and aluminum tariffs.  

“The court’s decision also raises questions on how U.S. importers can reclaim levies already paid and whether U.K. exporters can also receive a share of any rebate depending on commercial trading terms,” Bain said in a statement. “For the U.K., the priority remains bringing tariffs down wherever possible.”

Olof Gill, European Commission spokesperson for trade and economic security, said businesses on both sides of the Atlantic depend on “stability and predictability.”

“We remain in close contact with the U.S. Administration as we seek clarity on the steps they intend to take in response to this ruling,” Gill said. “We therefore continue to advocate for low tariffs and to work towards reducing them.”

Meanwhile, Dominic LeBlanc, Canada’s minister for U.S.-Canadian trade relations, said the decision “reinforces Canada’s position that the IEEPA tariffs imposed by the United States are unjustified.”

The Supreme Court on Friday struck down a huge chunk of President Donald Trump’s far-reaching tariff agenda, delivering a major rebuke of the president’s key economic policy.

The law that undergirds those import duties “does not authorize the President to impose tariffs,” the majority ruled 6-3 in the long-awaited decision.

The ruling is a massive loss for Trump, who has made tariffs — and his asserted power to impose them on any country at any time, without congressional input — a central feature of his second presidential term.

Trump’s legal stance “would represent a transformative expansion of the President’s authority over tariff policy,” the majority concluded. And they highlighted that Trump imposed the tariffs without Congress, which has the power to tax under the Constitution.

Chief Justice John Roberts delivered the opinion of the court. Justices Clarence Thomas, Samuel Alito and Brett Kavanaugh dissented.

The decision noted that before Trump, no president had ever used the statute in question “to impose any tariffs, let alone tariffs of this magnitude and scope.”

To justify the “extraordinary” tariff powers, Trump must “point to clear congressional authorization,” the court wrote. “He cannot.”

The ruling was silent on whether tariffs that have been paid under the higher rates will need to be refunded. That sum could total $175 billion, according to a new estimate from the Penn Wharton Budget Model.

Kavanaugh wrote in his dissent that the refund process “is likely to be a ‘mess,'” after predicting that the short-term impact of the court’s tariff ruling “could be substantial.”

Since retaking the White House, Trump has rapidly reshaped America’s long-standing trade relationships by imposing a staggering array of import duties that have touched nearly every country on earth.

Reaction to the ruling quickly poured in, with the loudest voices cheering the demise of the chaotic policy that has been blamed for raising prices and straining long-standing global alliances.

That announcement stoked a sudden market panic, and the tariffs were quickly put on pause. They have since been repeatedly tweaked, delayed and reimposed, adding confusion and further complexity to the administration’s tangled web of trade policies.

Other IEEPA-based tariffs include a set aimed at Mexico, Canada and China related to allegations that those countries have allowed the deadly drug fentanyl to flow into the U.S.

Trump, a fierce critic of America’s recent history of making free trade deals, has repeatedly praised tariffs as both a bountiful source of federal revenue and a key tool in negotiations with foreign partners and adversaries alike.

He has claimed foreign countries bear the cost of his tariffs, and he has downplayed concerns that the taxes lead to higher prices for Americans. His administration, however, has admitted that the duties are paid by U.S. importers.

Trump has claimed the tariff revenue has been so large that the duties may be able to replace the income tax. He has also floated the idea of sending Americans $2,000 tariff dividend checks.

“We have taken in, and will soon be receiving, more than 600 Billion Dollars in Tariffs,” he wrote in a recent Truth Social post.

Other estimates are significantly lower: The Bipartisan Policy Center, for instance, tallied U.S. gross tariff revenue in 2025 at about $289 billion. U.S. Customs and Border Protection said it had collected roughly $200 billion between Jan. 20 and Dec. 15.

For the IEEPA-specific tariffs, the administration said it has collected about $129 billion in revenue as of Dec. 10.

Ahead of the ruling, Trump and his administration talked up the consequences of the high court striking down the tariffs.

“If the Supreme Court rules against the United States of America on this National Security bonanza, WE’RE SCREWED!” Trump wrote on Jan. 12.

U.S. officials, including Treasury Secretary Scott Bessent, have stated they believed the Supreme Court would not undo the president’s “signature” economic policy.

The Trump administration has warned it would be “very wise” for Iran to make a deal, amid reports the White House is considering fresh military action against Tehran as soon as this weekend.

It comes shortly after Vice President JD Vance accused Iran of failing to address core U.S. demands during nuclear talks in Switzerland this week. Iran’s foreign minister previously reported progress in the talks, saying the two countries had reached an understanding over the “guiding principles” for the negotiations.

Speaking at a news briefing Wednesday, White House Press Secretary Karoline Leavitt said there were “many reasons and arguments that once could make for a strike against Iran,” noting that the two countries remain “very far apart” on some issues.

The U.S. president had a “very successful” operation last June, Leavitt said, when U.S. stealth bombers struck three Iranian nuclear facilities as part of “Operation Midnight Hammer.”

“The president has always been very clear though with respect to Iran or any country around the world, diplomacy is always his first option. And Iran would be very wise to make a deal with President Trump and this administration,” Leavitt said.

The White House has said it still hopes to reach a diplomatic resolution over Tehran’s nuclear program, although U.S. media has reported that the military could be prepared to strike Iran as early as the weekend.

The U.S., for its part, has built up a significant presence of air and naval assets, while Iran has conducted military drills in the strategically vital Strait of Hormuz and announced joint naval drills with Russia in the Sea of Oman.

Laura James, Middle East senior analyst at Oxford Analytica, described the current situation as “extremely dangerous,” with the U.S. and Iran “certainly closer” to an outright conflict than last week.

“The thing that is now a particular concern over the past 24 hours is the very rapid pace at which the United States is reinforcing its air power in the region. That, of course, can still be signalling and pressure for a particular diplomatic outcome,” James told CNBC’s “Access Middle East” on Thursday.

“But as more and more planes comes in and more and more equipment comes in, that signalling gets more and more expensive. And therefore, the payoff you want for it in diplomatic terms has to be larger — and there is simply no sign Tehran can offer the absolute minimum that Washington is likely to demand,” she added.

Oil prices

Energy market participants have been closely watching the outcome of the U.S.-Iran talks in Geneva, particularly as it relates to the Strait of Hormuz, a major international waterway that Iran partially closed on Tuesday citing “security precautions.”

Located in the gulf between Oman and Iran, the Strait of Hormuz is recognized as one of the world’s most important oil choke points.

About 13 million barrels per day of crude oil transited the Strait of Hormuz in 2025, accounting for roughly 31% of global seaborne crude flows, data provided by market intelligence firm Kpler showed.

Oil prices were higher on Thursday, extending gains after settling up more than 4% in the previous session.

International benchmark Brent crude futures with April delivery rose 1.5% to $71.41 per barrel, while U.S. West Texas Intermediate futures with March delivery stood 1.7% higher at $66.27.

— CNBC’s Lee Ying Shan contributed to this report.

Europe is “totally on the sidelines” on the global stage as “wrecking ball” politics has become the norm, the head of the continent’s biggest security forum has said.

Speaking to CNBC’s Annette Weisbach ahead of the Munich Security Conference (MSC), Wolfgang Ischinger, the organization’s chairman, said it was Europe’s “own fault” that its power on the global stage has been diminished.

“Europe has failed to speak with one voice to China and about China, Europe has failed with one voice, to come up with a clear concept about the future of the Middle East, including about how to deal or not to deal with the Iranian nuclear question,” said Ischinger, who is a former German ambassador to the U.S.

Earlier this week, the MSC published its 2026 report, for which Ischinger wrote the foreword. It warned that “the world has entered a period of wrecking-ball politics,” where “sweeping destruction … is the order of the day.”

The report said that U.S President Donald Trump was “at the forefront of those who promise to free their countries from the existing order’s constraints and rebuild stronger, more prosperous nations,” arguing he was just one movement “driven by resentment and regret over the liberal trajectory their societies have embarked on.”

Ischinger told CNBC that Europeans were “totally on the sidelines” on negotiations around Gaza and Ukraine.

“We have no role. Things have been decided by others,” he said. “When I look at the war in Ukraine, Europe has no place,” he said, adding the U.S. and Russia were leading discussions.

U.S. delegates have been helming peace talks with officials from Ukraine and Russia since late 2025, with European officials scrambling to maintain a say on how to end the four-year war between the two countries.

“Why the hell do we not have a place at the table? This is our continent. It’s our future,” Ischinger said on Friday. “The answer, of course, is not that Donald Trump is making a mistake. The answer … is that we have failed to speak with one voice.”

Ischinger added that he rejected “the blame game regarding the United States,” but for areas where Europe “clearly failed” to adopt a strategic position.

Delegates from all over the world are gathering for the Munich Security Conference on Friday. The event runs through Sunday.

Ischinger told CNBC that the “wrecking ball” was “being used by many” in addition to Trump, including right-wing extremist parties across Europe and Russian President Vladimir Putin.

But he called Trump “the single most prominent example” of someone who “questions existing arrangements and tries to replace them.” “That is for countries like Germany, which have been so dependent on the existing international rules … a worrisome development,” he added.

CNBC reached out to both the White House and the Kremlin for responses to the MSC’s commentary.

Transatlantic trust had also been damaged by Trump’s push for the U.S. to annex Greenland, Ischinger said.

After weeks of rhetoric on bringing the Arctic island — a Danish territory — under Washington’s control, Trump threatened to impose tariffs on European allies who stood in his way, before announcing a “deal” on Greenland had been reached.

Since Trump’s return to the White House, European leaders have been making commitments to drastically increase security spending. Last summer, European members of NATO agreed to raise defense spending to 5% of their individual national GDP — a move Trump had been pushing for for some time.

The spending plans have bolstered European defense primes, some of which have seen their shares more than double in value, while order backlogs have hit record levels.

Ischinger told CNBC Europe needed “to create a more consolidated, a more competitive, a more unified defense industry.”

The prospect of a U.S. attack on Iran has roiled oil prices this year, but analysts tell CNBC a strike would require more military commitment and be more complicated, than the U.S. is prepared for.

Tensions are high, and despite talks last week in Oman, both sides remain at an impasse. U.S. President Donald Trump’s pressure on the Iranian regime escalated after a brutal crackdown on anti-government protestors across the country last month.

Trump said this week he was considering sending a second aircraft carrier to the Middle East, even as Washington and Tehran prepare to resume talks. On Tuesday, he threatened Iran with “something very tough,” if it does not agree to Washington’s demands, which range from halting the country’s nuclear enrichment to cutting Tehran’s ballistic missile program.

The U.S. deployed the USS Abraham Lincoln carrier strike group to the Middle East in January. This brought the number of missile destroyers in the region to six, but, analysts say, this still wouldn’t be enough to topple the regime. Following through on his “something tough” threat would mean a prolonged conflict in a region Trump is wary of.

“U.S. forces in the region are not adequate to support a significant long-term military operation in Iran which would be necessary to achieve any major military objective,” Alireza Ahmadi, executive fellow at the Geneva Center for Security Policy, told CNBC.

Trump has also dialed up his pressure on the Islamic Republic, applying financial pressure to an economy already crippled by sanctions. Just last month, he vowed to impose tariffs on any country that acquires any goods or services from Iran.

But it is unclear what could come next. “President Trump is notoriously unpredictable,” Ali Vaez, director of Iran Project at Crisis Group, told CNBC but added Trump is aware “the Iran problem set does not lend itself to clean and easy military options.”

The White House claimed after strikes on three main nuclear sites last year that Iran’s nuclear facilities were “obliterated.” Iran moved to quickly repair the damage to ballistic missile sites but according to analysis from the New York Times, has made “limited fixes” to the major nuclear sites hit by the United States.

Iran has long claimed it does not have any plans to develop nuclear weapons. As talks restart between Washington and Tehran, Iran has offered to cap its enrichment at low levels. The U.S. has opposed the Iranians enriching any uranium since the nuclear deal collapsed in 2018.

While the U.S. has vowed to attack Iran if it resumes its nuclear and missile programs, it is unclear whether these sites would again be primed for attack. “Both options are likely to lead to a disproportionate Iranian retaliation, which could then turn the confrontation into a regional conflagration,” Vaez said.

The release of further Epstein files last week triggered a series of events that left U.K. Prime Minister Keir Starmer fighting for his political life, despite the fact that he never knew the late financier and sex offender.

Starmer is under pressure over his decision to appoint Peter Mandelson as U.S. ambassador, despite knowledge of Mandelson’s connections to Epstein. The latest document release by the U.S. Department of Justice revealed more messages between Mandelson and Epstein, including after Epstein had pleaded guilty in Florida to a state charge of felony solicitation of prostitution, a case that involved an underage girl.

Starmer, who is facing calls to step down, has apologized to the victims of Epstein for believing Mandelson’s “lies.”

Starmer held a pivotal meeting with Labour members of parliament afterwards, in which he reportedly said he was “not prepared to walk away.”

A spokesperson for the Prime Minister’s Office was not immediately available for comment.

Known as a behind-the-scenes fixer and nicknamed the “Prince of Darkness,” Mandelson was a Labour member of parliament from 1992 to 2004 and served in Blair’s cabinet.

He left parliament to become a European Commissioner before returning to Britain in 2008 to work with then-Prime Minister Gordon Brown, having been appointed to parliament’s unelected House of Lords.

After becoming prime minister in July 2024, Starmer appointed Mandelson as ambassador in Washington that December, a role he described at the time as “a great honor.” The appointment was controversial as Mandelson had twice previously resigned — in 1998 and 2001 — over scandals: one about not declaring a loan and another about allegedly influencing a passport application.

Starmer fired Mandelson from the ambassadorship in September, after Downing Street said new information had come to light about the extent of his association with Epstein.

The subsequent release of millions of files from the U.S. Department of Justice last week showed further links between Mandelson and Epstein. They prompted accusations that Mandelson had sent market-sensitive government information to Epstein following the 2008 global financial crisis.

One exchange appeared to show Mandelson giving Epstein advance notice of an impending 500 billion euro bailout for banks in 2010.

In a statement to U.K. broadcaster Sky News last month, Mandelson apologized for remaining friends with Epstein following his 2008 conviction.

“I was not culpable, I was not knowledgeable for what he was doing, and I regret, and will regret to my dying day, the fact that powerless women were not given the protection they were entitled to expect,” he said.

U.K. government borrowing costs jumped on Monday, amid growing pressure on Starmer.

By Tuesday, after many Cabinet ministers rallied around the prime minister, yields on U.K. government bonds, known as gilts, were moving lower.

The yield on the benchmark 10-year gilt was 3 basis points lower at 4.496%, while the 30-year gilt yield also fell by 4 basis points to settle at 5.309%.

Among the potential candidates to replace Starmer are left-leaning Angela Rayner, who resigned as deputy prime minister last autumn after a tax scandal, the current health minister, Wes Streeting, and former party leader Ed Miliband.

Andy Burnham, the current mayor of Greater Manchester, was recently blocked from standing in a special election that could have seen him return to parliament — paving the way for a potential leadership challenge.

Despite Burnham’s popularity, investors are wary of a pivot away from efforts by Starmer and his finance minister, Rachel Reeves, to shore up the U.K.’s public finances.

Kallum Pickering, chief economist at Peel Hunt, said in a note on Tuesday that Burnham “polls strongly” but “whether his successful regional economic policies translate into successful national policies is an open question — his past snipes that the U.K. is ‘in hock to the bond markets’ have alarmed investors.”

Pickering said the fact that Rayner remained under investigation for her tax affairs “hurts her chances — and risks the narrative of replacing one scandalised PM with another.” But he added: “Her popularity within the party suggests she may be able to consolidate the left with the moderates.”