Unpredictable agreements such as Ukraine’s rare earth minerals deal with the US cannot be the basis for the new world order, Donald Tusk has said.

The Polish prime minister criticised the pact struck by Washington and Kyiv, which still needs the final sign-off from Volodymyr Zelensky, the Ukrainian president, and is a key part of the US push to end the war with Russia.

On Wednesday, Mr Zelensky said that hinged on his looming talks with Donald Trump, as the Americans had offered no firm security guarantees against Russian aggression.

Mr Trump had demanded access to the minerals to claw back $500 billion of US wartime support given as grants to Ukraine – a figure Kyiv fiercely opposed and said was not part of the final deal.