A major crypto currency company has announced that Nigel Farage has made a £2m purchase of bitcoin in a strengthening of ties with the sector.

The Reform UK was filmed in a promotional video for Stack BTC, a crypto reserve business chaired by Liz Truss’s former chancellor Kwasi Kwarteng.

The company said the purchase was a “landmark moment” in British politics. It claimed Mr Farage is the first sitting MP and first UK political party leader to publicly buy bitcoin. Mr Farage had already invested £215,000 in Stack in March.

Mr Farage and Reform have pledged to liberalise the bitcoin market and have taken millions in major donations from crypto billionaires including Thailand-based Christopher Harborne and Hong Kong-based Ben Delo.

Meanwhile, Labour have moved to ban crypto donations to political parties and asked the Electoral Commission to investigate potential crypto donations that Mr Farage claims Reform has received but has not yet declared.

Stack, a London-based firm listed on the UK challenger stock exchange Aquis, operates by building a portfolio of companies and channelling their surplus cash into bitcoin. Its core objective is to establish a substantial bitcoin treasury through continuous accumulation of the digital currency.

Kwarteng, who oversaw the disastrous 2022 mini-budget with Liz Truss, became executive chair of Stack in October last year. He and his wife jointly own 5.4 per cent of the company.

Labour questioned why Mr Farage was investing his money with the “architect of Liz Truss’s disastrous mini Budget”.

Anna Turley, chair of the Labour Party, said: “Nigel Farage is hyping up a former Tory chancellor who crashed the economy, in a bid to line his own pockets.

“From Farage’s crypto-boosting to his deputy Richard Tice’s admission that his business didn’t pay the taxes it owed, Reform are more interested in themselves than in standing up for working people.

“While Labour is working to clear up the mess the Tories left, Nigel Farage is cosying up to the architect of Liz Truss’s catastrophic mini-budget. It tells you everything you need to know about whose side he’s on.”

It came as Mr Farage defended his deputy Richard Tice for the first time over allegations he had failed to properly pay tax on dividends.

Mr Tice, who is the party’s business spokesperson and jointly owns it with Mr Farage, has been accused of failing to pay tens of thousands of pounds in tax on dividends that were paid to him and his offshore trust.

Allegations in The Sunday Times suggested he received “at least £91,000 in excess payments” as a result of the failure.

Among the critics was tax expert Dan Neidle who claimed that Mr Tice’s “company broke the law”. He went on: “There was no ability to choose for different people to pay tax, months later than it should be paid. The law is the law. It’s not optional.”

He noted: “Mr Tice, owns a property company, Quidnet Reit [real estate investment trust]. From 2020 to 2022, it paid Tice and his trust £600k in dividends. Quidnet should have paid £120k of tax on those dividends. It didn’t.

“Reits and their investors don’t get to choose how and when tax is paid. The law required that the Reit pay tax on its dividends immediately, rather than waiting up to 21 months until its shareholders file and pay tax. The tax is still due.”

But Mr Farage dismissed Mr Neidle as “a Labour activist” and suggested that Mr Tice had in fact “most likely paid more tax than had his company paid corporation tax.”

He insisted the area of taxation was “extremely complicated” but said there was no suggestion Mr Tice had avoided tax.

He said: “If our biggest critic says that Richard Tice has not evaded or avoided tax, has paid the full amount, and actually maybe even a little bit more think about it then I’m satisfied with that.”

The press conference saw Mr Farage and his home affairs spokesman announce plans for an inquiry into the so-called “Boriswave” of immigration between 2020 and 2024 even though two of the prime movers in that period – former home secretary Suella Braverman and ex-immigration minister Robert Jenrick – have since defected to reform.

He claimed that the costs of a generation of non-EU migrants who came to Britain in the years after 2021 will be an “economic millstone” for the country.

The Reform UK leader said: “There is still time. There is still something we can do about this Boriswave. But if over a couple of million people get indefinite leave to remain over the course of the next 18 months, we will be putting around our necks an economic millstone that, frankly, will be catastrophic.”

He later defended ex-Conservatives who served in Mr Johnson’s government that had since defected to Reform UK.

Mr Farage said: “Of course, there are some that will say, ‘Ah, but you’ve got Suella Braverman, you’ve got Robert Jenrick in your party’.

“Yes, absolutely. And if you read what Suella has written on this, and you read what Robert has written on this, they tried from within to stop the disaster that really started properly in 2021 and that’s why they resigned or were fired.”

The Independent has asked Reform for comment on the crypto currency announcement.