Ukrainian President Volodymyr Zelenskyy got a hero’s welcome from British Prime Minister Keir Starmer on Saturday, just 24 hours after a fiery clash with US President Donald Trump turned his White House visit into a diplomatic disaster. Arriving at 10 Downing Street to cheers from a supportive crowd, Zelenskyy was swept into a warm hug by Starmer, who vowed the UK’s unshakable loyalty amid fears of a US pullback from Ukraine’s fight against Russia.

“You’ve got the full backing of the United Kingdom,” Starmer declared, pointing to the roaring supporters outside. “We’re with you and Ukraine for the long haul.” A visibly moved Zelenskyy thanked Starmer and the British public for standing by his war-torn nation, calling them true friends. The meeting came ahead of a crunch summit of European leaders in London on Sunday, now supercharged with urgency after Trump’s public dressing-down of Zelenskyy on live TV.

The White House showdown saw Trump and Vice President JD Vance tear into Zelenskyy, accusing him of ingratitude for US aid as he resisted pressure to cut a deal with Russia over Ukraine’s mineral wealth. No agreement was signed, and Zelenskyy bolted for London. Starmer, fresh off talks with the Ukrainian leader, later jumped on calls with Trump and French President Emmanuel Macron to steady the ship.

Originally slated for Sunday, Zelenskyy’s chat with Starmer was fast-tracked after the Washington chaos. On Sunday, he’ll meet King Charles III at Sandringham before heading to Lancaster House—a grand 200-year-old pile near Buckingham Palace—for the European huddle. With Trump’s threats to ditch Ukraine ringing in their ears, leaders are scrambling to figure out how to shield Kyiv—and themselves—if America walks away.