However, no security pledges for war-torn Ukraine were announced.
Speaking at a joint news conference with Trump, who has reached out to Russia, Starmer warned that any deal on Ukraine must not reward the aggressor.
"We agree—history must be on the side of the peacemaker, not the invader," Starmer said at the White House. "So the stakes, they could not be higher. And we're determined to work together to deliver a good deal."
He added: "We've discussed a plan today to reach a peace that is tough and fair that Ukraine will help to shape and that is backed by strength—to stop Putin coming back for more."
After his talks with Trump, Starmer invited more than a dozen European leaders, including Polish Prime Minister Donald Tusk, to a summit in London on Sunday to discuss "the need for Europe to play its part on defence and step up for the good of collective security."
Michał Owczarek has this report.
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