A former White House adviser excoriated Republican members of Congress at the impeachment inquiry into U.S. President Donald Trump on Thursday for promoting the “fictional narrative” that Ukraine meddled in the 2016 election.

Fiona Hill, the former specialist on Russia for the National Security Council, detailed the pressure campaign Mr. Trump orchestrated to get Kyiv to investigate both this conspiracy theory – that Ukraine had helped the Democratic Party – and Joe Biden in a bid to tarnish his political rivals ahead of next year’s presidential election.

She warned that such “falsehoods” about Ukraine, which Republican members of the House intelligence committee have repeated in hearings this week, only helped the Kremlin.

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“This is a fictional narrative that has been perpetrated and propagated by the Russian security services themselves,” Ms. Hill said. “I would ask that you please not promote politically driven falsehoods that so clearly advance Russian interests.”

Russian President Vladimir Putin and his government have pushed the Ukrainian interference conspiracy to deflect from their own 2016 meddling campaign, and to drive a wedge between Kyiv and its U.S. allies.

The session, which capped a week of incendiary hearings on Capitol Hill, also included testimony from a U.S. diplomat who said it was common knowledge in the U.S. embassy in Kyiv last summer that Mr. Trump was withholding US$400-million in military aid to Ukraine and an invitation to the White House for its President until the Ukrainians agreed to the probes he was demanding.

“Of course, the President is pushing for a Biden investigation before he’ll do these things the Ukrainians want,” said David Holmes, a staffer at the mission in Kyiv. “It was obvious what the President was pushing for.”

Both Mr. Holmes and Ms. Hill focused on the role of Gordon Sondland, the Trump-appointed ambassador to the European Union who was central to the pressure campaign.

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In one dramatic episode, Ms. Hill said she confronted Mr. Sondland for meeting Ukrainian officials without going through regular diplomatic channels. Ms. Hill said Mr. Sondland told her he was reporting directly to Mr. Trump, White House chief of staff Mick Mulvaney and Secretary of State Mike Pompeo.

“He was being involved in a domestic political errand, and we were being involved in national security foreign policy, and those two things had just diverged,” Ms. Hill said. “I did say to him … ‘Gordon, I think this is all going to blow up.’ And here we are.”

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On another occasion, she said, Mr. Sondland told her he had a deal with Mr. Mulvaney to trade an Oval Office invitation for Ukrainian President Volodymyr Zelensky for the investigations. This conversation, she said, took place in the Mess Room of the White House in front of two senior Ukrainian officials, presidential adviser Andrey Yermak and then-security adviser Alex Danylyuk.

When Ms. Hill passed this information to then-national security adviser John Bolton, she said, he told her to report it to White House lawyers. “Tell them I am not part of whatever drug deal Mulvaney and Sondland are cooking up,” Ms. Hill quoted Mr. Bolton saying.

Mr. Holmes, meanwhile, recounted that Mr. Sondland shut him out of a meeting with Mr. Yermak at the U.S. embassy in Kyiv on July 26 because Mr. Sondland did not want anyone in the room taking notes.

At a subsequent lunch on a restaurant terrace, Mr. Holmes said Mr. Sondland took out his mobile phone and called Mr. Trump at the White House. According to Mr. Holmes’s account, Mr. Sondland told Mr. Trump that Mr. Zelensky “loves your ass,” Mr. Trump asked “so he’s going to do the investigation?” and Mr. Sondland replied: “He’s going to do it. President Zelensky is going to do everything you want him to do.”

When Mr. Holmes asked Mr. Sondland for Mr. Trump’s views on Ukraine, Mr. Holmes said Mr. Sondland told him Mr. Trump did not care about the country and only cares about “big stuff that benefits the President – like the Biden investigation.”

Devin Nunes, the top Republican on the committee, fired back at Ms. Hill’s criticism of the Ukraine narrative Mr. Trump and he support. “It’s entirely possible for two separate nations to engage in election meddling at the same time,” he said.

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All U.S. intelligence agencies have found that Russia interfered in the 2016 election. They have not found any basis for the theories on Ukraine.

No further hearings are currently scheduled. House Democrats could begin drafting articles of impeachment as soon as next week. If they are passed by the Democratic-controlled House, Mr. Trump would face trial in the Republican-held Senate. It would take a two-thirds majority to throw him out of office.

Adam Schiff, the Democratic chair of the committee, argued Mr. Trump’s actions were even worse than those of Richard Nixon, who resigned in the face of an impeachment inquiry in 1974, because they had compromised the role of the United States as an international defender of democracy in the face of Russian aggression.

“We are the indispensable nation, we still are. People look to us all over the world,” he said in his closing statement. “Increasingly, they don’t recognize what they see.”

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