Mr. Trump specifically asked his Ukrainian counterpart to “do us a favor” by looking into an unsubstantiated theory pushed by Mr. Giuliani holding that Ukrainians had some role in the emails stolen from the Democratic National Committee.
“I would like to have the attorney general call you or your people and I would like you to get to the bottom of that,” Mr. Trump said on the call, referencing Robert S. Mueller III, the special counsel in the Russia case. “Whatever you can do, it’s very important that you do it, if that’s possible.”
Mr. Trump’s allies argue that he was not exerting improper pressure on Mr. Zelensky, but mentioned Mr. Barr because the Justice Department was already reviewing the origins of the inquiry into Russia’s 2016 election meddling.
The president’s mentions of Mr. Barr and Mr. Giuliani were the most striking part of a half-hour conversation in which the two men discussed a series of issues. But several times, Mr. Trump steered the conversation back to Mr. Barr, Mr. Giuliani and Mr. Biden.
There was no reference, implicit or explicit, to the $391 million in foreign aid that Mr. Trump had told Mick Mulvaney, the acting White House chief of staff, to put a hold on several days before the call took place.