President Trump gave President Vladimir Putin a warm public reception, effectively ending his diplomatic isolation over the past three years for his invasion of Ukraine. But Mr. Putin did not agree to stop the war.

President Trump struck a remarkably unconcerned tone when asked to address the horrors of war, raising questions about whether he has the leverage to convince Vladimir V. Putin to…

Once a vague proposal for a territorial swap gained clarity, a worried President Volodymyr Zelensky worked to rally allies before Friday’s Trump-Putin summit.