As Germany’s chancellor, Friedrich Merz, sat beside him watching in silence, President Trump compared Russia and Ukraine to two fighting children who needed to work out their differences for a while before anyone could intervene.

“Sometimes you see two young children fighting like crazy,” Mr. Trump said on Thursday in an Oval Office news conference. “They hate each other, and they’re fighting in a park, and you try and pull them apart. They don’t want to be pulled. Sometimes you’re better off letting them fight for a while and then pulling them apart.”

“And I gave that analogy to Putin yesterday,” Mr. Trump added. “I said, ‘President, maybe you have to keep fighting and suffering a lot, because both sides are suffering, before you pull them apart, before they’re able to be pulled apart.’”

Mr. Merz, who became Germany’s chancellor last month, had come to Washington hoping to persuade Mr. Trump to play a more active role in defending Ukraine by bringing unrivaled U.S. power to the task of forcing Russia to end its invasion of its smaller neighbor. But he got a very different response. Mr. Trump essentially threw up his hands, saying that there was nothing the United States could do right now to bring the Russia-Ukraine war to an end.

Mr. Trump repeatedly promised during the presidential campaign that he could make peace between the warring nations within 24 hours, but he now says he was being sarcastic.

Four months into his second term, Mr. Trump is talking about the war as if he is a bystander. When a reporter asked him at Thursday’s news conference whether he was going to put more sanctions on Russia, as he had previously threatened, Mr. Trump equivocated. He suggested he would know when the moment had arrived to pile on more pressure, but that it hadn’t yet.