In a newly released impeachment inquiry transcript, a top State Department official told congressional investigators that President Donald Trump tried to pressure Ukrainian President Volodymyr Zelenskiy to announce a corruption investigation targeting Trump’s political foes.

“POTUS wanted nothing less than President Zelenskiy to go to [a] microphone and say investigations, Biden, and Clinton,” said Deputy Assistant Secretary of State George Kent—alluding to former Vice President Joe Biden, who may become Trump’s opponent in next year’s presidential election, and former Secretary of State Hillary Clinton, who ran against Trump in 2016.

Kent added that he wasn’t certain what the deal hinged on. But the testimony of William B. Taylor, the U.S. chargé d’affaires in Ukraine, sheds some light on that: In a transcript released Wednesday, he told investigators that it was his “clear understanding” that Ukraine would not receive security aid “until the President committed to pursue the investigation.”

The impeachment inquiry is delving into whether Trump withheld congressionally authorized aid to Ukraine in order to compel Zelenskiy to publicly pursue probes into Burisma Holdings, the energy company where Biden’s son sat on the board, and into possible Ukrainian interference on behalf of Clinton’s presidential campaign.

The White House has released a summary of a July phone call between Trump and Zelenskiy. In it, Trump seemed to allude to the aid package more than once, but he never mentioned it explicitly. The administration froze the aid this summer without explanation, and it did not disburse the appropriated funds until September 11.

Gordon Sondland, who became ambassador to the European Union after donating $1 million to Trump’s inaugural fund, initially testified that he had no knowledge of any such efforts. He revised those statements on November 4, the day before his closed-door testimony was to be released, writing that he recalled telling a top Zelenskiy adviser that the aid would not come through unless the Ukrainian president announced the investigations.

“I now recall speaking with [Andriy] Yermak,” he wrote. “I said that resumption of U.S. aid would likely not occur until Ukraine provided the public anti-corruption statement that we had been discussing for many weeks.”

According to Taylor’s testimony, those efforts were consciously spearheaded by Rudy Giuliani, Trump’s personal lawyer, with assistance from Sondland, Energy Secretary Rick Perry, and former special envoy Kurt Volker. On a June phone call, when facilitating plans for a meeting between Trump and Zelenskiy—a meeting the Ukrainian leader was highly keen on having—Sondland requested that “no one was transcribing or monitoring” the conversation as Zelenskiy joined, according to Taylor. “By mid-July,” Taylor continued, “it was becoming clear to me that the meeting President Zelenskiy wanted was conditioned on the investigations of Burisma and alleged Ukrainian interference in the 2016 U. S. elections.”

It was also apparent “that this condition was driven by the irregular policy channel I had come to understand was guided by Mr. Giuliani.”

Kent reinforced those remarks in his deposition, claiming that Giuliani engaged in a “campaign of lies” to smear Marie Yovanovitch, the former U.S. ambassador to Ukraine, because she would not force Zelenskiy’s hand. The president’s attorney “had been carrying on a campaign for several months full of lies and incorrect information about Ambassador Yovanovitch,” Kent said. “His assertions and allegations against former Ambassador Yovanovitch were without basis, untrue, period.” Yovanovitch was abruptly removed from her post in May.

On Wednesday, Giuliani once again confirmed that he pushed for the corruption investigation, though he contradicted some of his previous claims on the subject. “The investigation I conducted concerning 2016 Ukrainian collusion and corruption,” he tweeted, “was done solely as a defense attorney to defend my client against false charges, that kept changing as one after another were disproven.” Contrast that with his September 24 appearance on Laura Ingraham’s Fox News program, in which he said he pursued the probe at the government’s behest.

“You know who I did it at the request of? The State Department,” Giuliani told Ingraham. “I never talked to a Ukrainian official until the State Department called me and asked me to do it. And then I reported every conversation back to them.”

Whichever is correct might not matter if it becomes clear that the aid was explicitly conditioned on a favor for the president’s personal gain. “I had concerns that there was an effort to initiate politically motivated prosecutions that were injurious to the rule of law,” Kent testified, “both in Ukraine and the U.S.”