President Donald Trump is holding hastily arranged talks Monday with Ukrainian President Volodymyr Zelensky and a host of European leaders — a rarity at the White House — as he seeks to negotiate an end to Russia’s war in Ukraine.

P resident Donald Trump told President Volodymyr Zelensky of Ukraine on Monday that the United States would join Europe in providing security guarantees to Kyiv as part of a broader peace deal with Russia, the clearest signal yet that the White House is prepared to underwrite Ukraine’s long-term defense while pressing for negotiations with Moscow.