Keir Starmer faces the biggest test of his premiership today as he tries to persuade Donald Trump to stand by Ukraine and Western allies. Sir Keir has been appealing for Mr Trump to stop Vladimir Putin 'coming again' after a rushed peace deal, arguing America must help guarantee the terms. He is also pitching for the UK to be spared tariffs as the White House goes on the attack over what it claims are unfair trade arrangements with the rest of the world. The PM's visit to the White House today is part of a frantic European effort to persuade President Trump not to abandon Ukraine and Europe.