Mr. Trump has also showed a clear desire for a peace deal on Ukraine, part of his longstanding effort to remove an issue that has driven a wedge between Russia and the West, and has made his cozy relations with Russian President Vladimir V. Putin harder to defend.

Soon after the July 25 phone call in which he urged Mr. Zelensky to investigate his political rivals — the call at the heart of the impeachment inquiry — Mr. Trump seemed confident that he would get a peace deal on Ukraine after all.

“I think he’s going to make a deal with President Putin, and he will be invited to the White House,” Mr. Trump said of the Ukrainian president.

But Mr. Trump has not pressed Russia and sided with Ukraine in the negotiations in the way Mr. Zelensky has urged. To the contrary, at a news conference in New York last month, Mr. Trump backed away from Mr. Zelensky and his troubles in the war, telling the Ukrainian leader, “I really hope you and President Putin get together and can solve your problem.”

By distancing himself from Mr. Zelensky in negotiations, Mr. Trump has made it harder for the Ukrainian government to defend the concessions it is making to end the war.

To revive settlement talks, Mr. Zelensky has already ordered his troops to pull back at some locations on the front line, a move that earned derision from his domestic critics, who called it a capitulation to Russia. Tens of thousands of people in Kiev, the capital, protested the decision this month in Independence Square, the site of the demonstrations that toppled Ukraine’s pro-Kremlin president five years ago.

Here in eastern Ukraine, the war is far from over. On a crystalline fall day, the contact line, as the front is known, opened onto a meadow of dry grass, stretching a few hundred yards to the opposing positions in a tree line, the oaks and maples in the brilliant autumn colors of orange and yellow.