WASHINGTON — President Donald Trump’s hand-picked diplomat to Europe told congressional investigators Wednesday that there was an explicit “quid pro quo” tying a White House visit to Trump’s push for investigations into his political rivals, and that he and other officials pressured Ukraine on Trump’s orders.

Appearing at a hearing in the Trump impeachment inquiry, Gordon Sondland, a Trump supporter and the U.S. ambassador to the European Union, shared text messages and other communications that show coordination of the pressure campaign with top officials at the White House and State Department, including Vice President Mike Pence and Secretary of State Mike Pompeo.

“Everyone was in the loop,” Sondland said.

His explosive testimony was the first to directly tie Trump to the Ukraine pressure campaign, and it undercut one of Republicans’ main defenses: their contention that Sondland and Trump’s personal attorney, Rudy Giuliani, were driving the push for investigations in Ukraine without Trump’s approval.

“Mr. Giuliani was expressing the desires of the president of the United States, and we knew that these investigations were important to the president,” Sondland, speaking in a calm, even tone, told the House Intelligence Committee.

And Sondland said he and others pushed Ukraine to announce investigations of Vice President Joe Biden and a discredited conspiracy theory about Ukrainian interference in the 2016 presidential election “because the president directed us to do so.”

“Was there a quid pro quo?” Sondland said, regarding Ukrainian President Volodymyr Zelensky’s desire for a White House meeting and Trump’s push for investigations. “The answer is yes.”

Sondland said he later “came to believe” that security aid that was vital to Ukraine also depended on the country’s leaders announcing the investigations Giuliani “had demanded.”

Sondland and others “worked with Mr. Rudy Giuliani on Ukraine matters at the express direction of the president of the United States,” Sondland said in his 19-page opening statement. “We did not want to work with Mr. Giuliani. Simply put, we played the hand we were dealt. We all understood that if we refused to work with Mr. Giuliani, we would lose an important opportunity to cement relations between the United States and Ukraine. So we followed the president’s orders.”

After weeks of closed-door depositions, Democrats have been building a public case that Trump abused his power by withholding a coveted White House visit and congressionally approved military aid to Ukraine while pushing for the investigations. Trump has repeatedly denied any wrongdoing, and Republicans in Congress have dismissed the impeachment inquiry as illegitimate, even as a growing number of witnesses have bolstered the allegations against Trump.

In questioning Sondland, Republicans emphasized his acknowledgement that Trump never explicitly told him that military aid was contingent on Ukraine announcing the investigations.

“A lot of it is speculation, a lot of it is your guess, and we’re talking about impeachment of the president of the United States” Republican counsel Steve Castor said.

Reading from hand-written notes as he departed the White House on Wednesday morning, Trump pointed to Sondland’s testimony that Trump had told him at one point that he wanted "nothing: from Ukraine.

“This is the final word from the president of the United States. I want nothing," Trump said. As for Sondland, Trump said: “I don’t know him very well. I have not spoken to him much. This is not a man I know well. He seems like a nice guy though.”

Just last month, Trump praised Sondland as “a really good man and great American."

After his opening statement, the Democrat leading the inquiry, Rep. Adam Schiff (D., Calif.) told reporters “it goes right to the heart of the issue of bribery as well as other high crimes and misdemeanors.”

Another Trump critic, former Republican Rep. Justin Amash (I., Mich.) tweeted, “Is there a mercy rule for congressional hearings?”

Sondland, unlike other witnesses who have testified so far, had direct contact with Trump over Ukraine, and arrived in his diplomatic post explicitly because of his ties to Trump, rather than any history of diplomatic expertise. He described himself as “a lifelong Republican.”

The Oregon hotel magnate donated $1 million to Trump’s inauguration, and arrived Wednesday as the most anticipated witnesses of the House impeachment inquiry, and the biggest wild card. Even Wednesday morning, lawmakers in both parties were unsure exactly what he would say and how far he would — or wouldn’t — go in implicating Trump. In private depositions Sondland initially downplayed any role in the scheme to pressure Ukraine, only to revise his testimony when it was contradicted by other witnesses.

Sondland said there was a clear connection between a White House visit or phone call for Zelensky, seen as crucial to establishing his standing as Ukraine’s new leader, and Zelensky agreeing to announce an investigation into Burisma, the energy company where Joe Biden’s son, Hunter, was a board member.

He was less direct when it came to the military aid. He said he came to understand that the aid was also tied to the investigations, and that he never heard of any other reason for its delay, but that Trump never made that connection explicit to him.

By September, “it was abundantly clear to everyone that there was a link,” he said at one point.

Earlier, however, in response to a Democratic attorney’s question, he said, “The aid was my own personal guess based again on your analogy: two plus two equals four. ... I never heard from President Trump that aid was conditioned on the announcement" of the investigations.

His conclusion matched those of several other career diplomats who reached the same exact conclusion: that the aid was being blocked until investigations were announced.

Sondland also said that he understood that Zelensky did not have to actually carry out the requested investigations to get a White House meeting, only publicly announce them. That point could undermine the GOP argument that Trump was delaying aid because he wanted to root out corruption, and bolster Democrats’ contention that Trump only wanted a campaign talking point that would damage Biden, a front-runner for the party’s presidential nomination.

Trump, in a July 26 phone call, specifically asked Sondland about the investigations Trump had requested from Ukraine’s president in a now infamous call the day before, according to another diplomat who overheard the conversation as Sondland held the phone away from his ear. Sondland later told the aide, David Holmes, that Trump “doesn’t give a s--t about Ukraine,” and was focused on “big stuff" that benefits him, like "the Biden investigation that Mr. Giuliani was pushing,” Holmes testified Nov. 15.

Sondland, according to Holmes, had assured Trump that the investigation tarring Biden would go forward.

Holmes’ account suggests that Trump continued emphasizing the investigations after his July 25 call with Zelensky, and was personally invested in the Giuliani’s effort. Sondland confirmed most of Holmes’ account during his testimony on Wednesday. Holmes is scheduled to testify publicly Thursday.

Sondland has shifted his accounts over the course of the investigation. In a private deposition, he initially downplayed his contacts with Trump and his role in the alleged plot to hold back aid unless Ukraine agreed to investigate Biden and his son. Sondland said he had rarely spoken with Trump.

But when other officials contradicted him, Sondland revised his testimony in early November, acknowledging telling Ukrainian leaders "that resumption of the U.S. aid would likely not occur until Ukraine provided the public anticorruption statement that we had been discussing for many weeks.”

At the time, however, he still left out the July 26 call with Trump.

Sondland acknowledged Wednesday that his testimony has “not been perfect,” and blamed the Trump administration’s refusal to allow him to access relevant materials or work with his staff to prepare.