Trump asked Volodymyr Zelenskyy whether Ukraine could strike Moscow, an inquiry that the White House says was merely a question but one that came hours after he voiced frustration at Putin’s refusal to accept a ceasefire.

The time frame for the further arms deliveries, which European countries have agreed to pay for, is crucial. Russia is making a summer push to break through along the 620-mile front line, and its drones and missiles are hammering Ukrainian cities more than at any time in the war.