The British foreign secretary, Yvette Cooper, will urge Sudan’s warring parties to “cease bloodshed” during a major conference on Wednesday, which analysts believe is unlikely to deliver a significant step towards peace.

The talks in Berlin – held on the third anniversary of the start of Sudan’s ruinous war – are expected to help address a catastrophic funding shortfall that is compounding the world’s worst humanitarian crisis.

Overall, just 16% of the humanitarian funding needed for Sudan this year has been provided by the international community as the crisis in Iran continues to dominate diplomatic channels.

Britain is among the countries attending the conference that are set to announce new funding for Sudan. Cooper will unveil a doubling of UK aid to £15m for Sudanese frontline responders such as the grassroots volunteer network known as Emergency Response Rooms.

With the war now entering its fourth year, and with no sign of hostilities abating between the paramilitary Rapid Support Forces (RSF) and the Sudanese army, latest assessments indicate more than 19 million people face acute hunger as a result of the fighting, while some areas are at risk of famine.

The latest assessment from the Integrated Food Security Phase Classification (IPC) found “emergency” levels of hunger across much of North Kordofan, West Kordofan, South Kordofan and North Darfur, while levels in some communities remained “catastrophic”.

It added that emergency levels of hunger were expected to spread over the coming months and that the number of people needing humanitarian aid was expected to reach 22-23 million.

Despite the scale of the suffering, Cooper hopes that an end to the fighting is achievable. “Today, in Berlin, I will call for the international community to join in a shared resolve: to secure a ceasefire and a diplomatic solution, to stop the suffering, and allow the people of Sudan to determine their own peaceful future,” she said.

Political momentum appears to have stalled as sources say talks between the so-called Quad nations, headed by the US along with Egypt and Saudi Arabia, which back the army, and the UAE, the RSF’s principal patron, have failed to yield “meaningful progress”.

Relations between Riyadh and Abu Dhabi in particular have deteriorated with acrimony emerging after clashes in Yemen over their respective proxy forces in December. However, the expected appearance in Berlin of Donald Trump’s political adviser on Africa, Massad Boulos, has prompted hopes that they can be galvanised.

One source attending the conference said: “We don’t expect anything major, certainly not on the political level.”

In the absence of any diplomatic breakthrough, the expert consensus is that Sudan’s war will worsen, particularly in the Kordofan region, which is at the centre of the fighting.

Paul Byars, Sudan director of the Danish Refugee Council, said: “I think there’ll be a worsening of the conflict in the Kordofan. Neither side will give up, which means they’ll keep taking and retaking territory.”

Technology is also likely to intensify bloodshed, with the increasing use of drones meaning that the traditional halt in fighting during Sudan’s imminent rainy season is less likely.

On Tuesday the UN said nearly 700 civilians have been reported killed in drone strikes in Sudan since January.