WASHINGTON — U.S. Ambassador to the European Union Gordon Sondland will tell Congress on Thursday that Rudy Giuliani told him President Donald Trump wanted Ukraine’s new government to investigate both the 2016 election and a natural gas firm tied to Hunter Biden, according to prepared testimony obtained by NBC News.

Sondland will testify that Giuliani, Trump’s personal lawyer, even mentioned getting the Ukrainians to investigate "the DNC server" — a reference to a Democratic National Committee computer that plays prominently in a debunked conspiracy theory about Ukrainian interference in 2016.

For full coverage of the impeachment inquiry, download the NBC News app

The ambassador is expected to tell House investigators that he ultimately learned that Giuliani, far from freelancing, was advancing Trump’s goals when he pushed for Ukraine to investigate the president’s political opponents.

"My understanding was that the president directed Mr. Giuliani’s participation, that Mr. Giuliani was expressing the concerns of the president," Sondland plans to say, according to the prepared testimony.

A key figure in the unfolding impeachment inquiry, Sondland had no diplomatic experience before Trump nominated him in 2017 to become ambassador to the E.U., a club of nations that does not include Ukraine. He was a wealthy hotelier who donated about $1 million to Trump’s inaugural committee and refers to himself in his prepared testimony as a “lifelong Republican.”

Nonetheless, Sondland casts blame directly on the president in the 18-page statement he plans to read to House lawmakers before answering their questions in the closed-door session. He also chastises his employer — the State Department — for trying to block his testimony.

In the prepared testimony, he repeatedly says he was "disappointed" in Trump’s decision-making on Ukraine and Giuliani’s involvement and asserts the president was in a "bad mood" the day Trump told Sondland by phone there were no quid pro quos involved in granting Ukrainian President Volodymyr Zelenskiy a coveted meeting with Trump.

Although likely to be challenged by lawmakers on several fronts, Sondland in his testimony paints a damning portrait of a troika of senior officials — Sondland, Energy Secretary Rick Perry and former Ukraine envoy Kurt Volker — begrudgingly engaging with Giuliani against their better instincts, out of desperation to advance U.S.-Ukraine relations.

President Donald Trump is joined by Gordon Sondland, the U.S. ambassador to the European Union as he arrives at Melsbroek Air Base, in Brussels, Belgium, on July 10, 2018. Pablo Martinez Monsivais / AP file

While Sondland’s timeline of events largely matches the one described by others who have already testified, his version absolves him of any wrongdoing or of having any foreknowledge of a scheme to use U.S. foreign policy to advance Trump’s political interests. His characterization is at stark odds with both the testimony of other officials and with written records obtained by the House in its impeachment inquiry.

"I knew that a public embrace of anti-corruption reforms by Ukraine was one of the pre-conditions for securing a White House meeting with President Zelenskiy," Sondland is expected to say, according to the prepared testimony. He’ll argue that because advocating good governance in Ukraine has been a U.S. priority for decades, "nothing about that request raised any red flags."

"I did not understand, until much later, that Mr. Giuliani’s agenda might have also included an effort to prompt the Ukrainians to investigate Vice President Biden or his son or to involve Ukrainians, directly or indirectly, in the president’s 2020 re-election campaign," Sondland wrote in the prepared testimony.

There is no evidence of corruption by either Biden.

Sondland’s depiction of a Trump-ordered campaign to pressure Zelenskiy to open an investigation adds to a growing body of testimony corroborating the underlying allegations contained in a whistleblower’s complaint that led the House to launch impeachment proceedings late last month. Trump has maintained he did "nothing wrong" and that all his efforts on Ukraine were both legal and appropriate.

Yet George Kent, a top State Department official for Europe, told lawmakers this week that he was sidelined by "the three amigos" — Sondland, Perry and Volker — and told to "lay low" after he raised concerns about Giuliani, NBC News reported. Former top State Department adviser Michael McKinley testified that he resigned this month in part because he was "disturbed by the implication that foreign governments were being approached to procure negative information on political opponents."

Fiona Hill, until recently the top Europe official in Trump’s White House, testified this week that Giuliani and Sondland circumvented National Security Council officials to run a shadow Ukraine policy. She described hearing Sondland tell visiting Ukrainian officials in June that Trump would grant Zelenskiy a visit if he opened an investigation and later mentioning Burisma after escorting the Ukrainians to the White House basement. Burisma Holdings is the Ukrainian gas company whose board the former vice president's son Hunter Biden joined in 2014.

And Volker, the envoy for Ukraine negotiations who resigned last month, turned over text messages to Congress showing himself, Sondland and a top Zelenskiy aide discussing exact language that Zelenskiy should utter in announcing the investigation sought by Trump.

In one text exchange, acting Ambassador to Ukraine Bill Taylor expressed alarm that the Trump administration was conditioning the release of U.S. military assistance to Ukraine on help with Trump’s re-election campaign, calling it "crazy."

Several hours later, Sondland texted back, telling Taylor that Trump "has been crystal clear, no quid pro quos of any kind." He suggests they stop discussing the matter via text message.

But Sondland plans to tell Congress that any suggestion he was trying to avoid creating a written record of their conversation is "completely false."

"I simply prefer to talk rather than to text," Sondland will say, according to the prepared testimony.

In a letter, obtained by NBC News, sent to the chairmen of the House Intelligence, Foreign Affairs and Oversight and Reform committees, Sondland’s attorneys explained that he was unable to turn over documents — including his communications — that they requested because they have been given to the State Department.

But they added that Sondland “has encouraged the State Department to provide the Committees with the requested documents in advance of his deposition. He strongly believes that disclosure will lead to a more fulsome and accurate inquiry into the matters at issue and will corroborate the testimony that he will give in key respects.”

Not only will Sondland assert he never heard the Bidens mentioned in any White House discussions, but he’ll also say he doesn’t recall any discussions about withholding military aid in exchange for help with Trump’s re-election. His prepared statement suggests that Taylor’s Sept. 9 text message was the first he learned about that concern.

"Taking the issue seriously, and given the many versions of speculation that had been circulating about the security aid, I called President Trump directly. I asked the president: 'What do you want from Ukraine?'" Sondland will tell Congress. "The president responded: 'Nothing. There is no quid pro quo.'"

Sondland goes on to say: "The president repeated: 'no quid pro quo' multiple times. This was a very short call. And I recall the president was in a bad mood."

Sondland will also testify that several months before that exchange, in May, he joined Perry, Volker and GOP Sen. Ron Johnson of Wisconsin in the Oval Office to brief Trump on their recent trip to Kyiv for Zelenskiy’s inauguration. He’ll say the returning delegation wanted Trump to grant Zelenskiy a White House visit but that Trump was "skeptical" about Zelenskiy’s seriousness in addressing corruption.

"He directed those of us present at the meeting to talk to Mr. Giuliani, his personal attorney, about his concerns," Sondland will say. "It was apparent to all of us that the key to changing the president’s mind on Ukraine was Mr. Giuliani."

In a rare critique of the president by one of his own political appointees, Sondland is expected to tell lawmakers that he, Perry and Volker were "disappointed" by that May 23 meeting and were "also disappointed by the president’s direction that we involve Mr. Giuliani."

Indeed, much of Sondland’s statement to Congress appears aimed at shifting the blame for any deviations from proper procedure on others: Giuliani, Hill, former national security adviser John Bolton and Trump himself. Sondland says he would never have recommended that "Giuliani or any other private citizen" be involved in foreign policy and only did so "given the president’s explicit direction."

National security adviser John Bolton with President Trump in the Oval Office on Sept. 28, 2018. Oliver Contreras / The Washington Post via Getty Images file

NBC News reported this week that Bolton was so concerned when Sondland told Ukrainian officials that Trump would meet with Zeleneskiy if he opened an investigation that he directed Hill, the Europe expert, to report the situation to the top National Security Council lawyer.

But, according to the prepared testimony, Sondland will say that Bolton and Hill never raised any concerns to him about Ukraine policy. He’ll state that he was "surprised and disappointed" by Hill’s reported "critical comments" about him and believes her testimony must have been "the product of hindsight."

Further minimizing his own role in the Ukraine matter, Sondland will say he only recalls meeting Giuliani once and speaking to him by phone just two or three times — for only a few minutes each. He’ll say it was Perry and Volker who "took the lead on reaching out to Mr. Giuliani, as the president had directed."

As for the public statement committing to an investigation that he and Volker discussed having Ukraine’s government issue, Sondland will say he recalls it being written mostly by the Ukrainians, with Volker’s "guidance" and Sondland’s assistance "when asked."

Text messages given by Volker to Congress showed Volker proposing to Sondland that they get Zelenskiy to refer to "alleged involvement of some Ukrainian politicians" in interference in U.S. elections.

"We intend to initiate and complete a transparent and unbiased investigation of all available facts and episodes, including those involving Burisma and the 2016 U.S. elections," Volker and Sondland agreed that the Ukrainian president should say at a news conference.

Trump has long promoted the baseless theory that Ukraine — not Russia — was responsible for 2016 election meddling. Zelenskiy never did make the statement.

According to the prepared testimony, Sondland will also offer effusive praise for former Ambassador to Ukraine Marie Yovanovitch, who was ousted by Trump in May amid a smear campaign promulgated by Giuliani, his associates and Ukraine’s then-prosecutor general. Trump, in the July 25 phone call with Zelenskiy that prompted the whistleblower complaint, refers to Yovanovitch as "bad news."

"I found her to be an excellent diplomat with a deep command" of Ukraine issues, Sondland plans to say, calling her a "delight" to work with and insisting he never participated in any campaign to disparage or dislodge her. He plans to add: "I regretted her departure."

Although Sondland will assert that Secretary of State Mike Pompeo supported his involvement on Ukraine — even sending him a "great work" congratulatory note and encouraging him "to keep banging away" — he also sharply criticizes the State Department in his prepared statement.

Under Pompeo, the State Department initially blocked Sondland’s testimony by directing him not to appear via an email to his lawyers just hours before his scheduled hearing last week. Sondland will say that the decision "disappointed" him.

Sondland’s rescheduled deposition Thursday is occurring under formal subpoena from the House, which Sondland will say "supported my appearance." He also plans to tell lawmakers he has not shared his prepared statement with either the White House or the State Department in advance of Thursday’s hearing.

"Some may want me to say things to protect the president at all costs; some may want me to provide damning facts to support the other side. But none of that matters to me. I have no interest in pursuing higher office or taking political shots," Sondland will say, according to the prepared testimony. "These are my own words."