US House of Speaker Nancy Pelosi said on Thursday that President Donald Trump admitted that he took bribery in the Ukraine scandal at the heart of a Democratic-led enquiry, accusing him of an impeachable offence under the US Constitution.

During a press briefing, Pelosi said a day after the first public hearing in the impeachment enquiry, “The bribe is to grant or withhold military assistance in return for a public statement of a fake investigation into the elections. That’s bribery”.

Pelosi further said, “What the president has admitted to and says it’s ‘perfect,’ I say it’s perfectly wrong. It’s bribery” (sic).

The money, approved by Congress to help a US ally combat Russia-backed separatists in the eastern part of the country, was later provided to Ukraine.

On Friday, another central figure – former US Ambassador to Ukraine Marie Yovanovitch is due to testify in the second public hearing in the inquiry.

On Wednesday, Trump described the impeachment probe against him as “witch hunt”, saying he was “too busy” to watch it.

Trump said while responding to the questions that he did not watch the impeachment proceedings against him and accused House Democrats of using “television lawyers” to conduct their questioning.

Earlier in the month, President Trump opposed impeachment enquiry, saying that there should be no public hearings during the House of Representatives’ impeachment enquiry against him, and directed White House Chief of Staff Mick Mulvaney not to appear before the committees investigating Trump’s phone call to Ukraine.

Trump administration had ordered officials not to participate in the House enquiry. But lawmakers have spent weeks hearing from current and former government witnesses, largely from the State Department, as one official after another has relayed his or her understanding of events.

Late September, the impeachment inquiry, which House Speaker Nancy Pelosi initiated over a complaint by an anonymous whistleblower, is looking into White House’s alleged efforts to withhold military aid to have Ukraine investigate a Trump’s political rival, Joe Biden.

The focus of the inquiry is a July 25 phone call in which Trump asked Ukrainian President Volodymyr Zelenskiy to investigate Democratic rival Joe Biden and the former vice president’s son Hunter, who had served as a board member for a Ukrainian energy company called Burisma.

Trump also asked Zelenskiy to investigate a debunked conspiracy theory embraced by some Trump allies that Ukraine, not Russia, interfered in the 2016 US election.

Last month, US former national security advisor was so alarmed by a White House–linked effort to pressure Ukraine to investigate Democrats, he told aide Fiona Hill to alert the National Security Council’s chief lawyer, Hill told House impeachment investigators in her 10-hour deposition.

(With inputs from agency)