Pelosi further said, "What the president has admitted to and says it's 'perfect, ' I say it's perfectly wrong".
"That he is not above the law", Ms Pelosi said.
The day's first two witnesses - Bill Taylor, the top USA diplomat in Ukraine, and George Kent, the deputy assistant secretary of state for European and Eurasian affairs - began with opening statements echoing their earlier closed-door testimony about their alarm over efforts to get Ukraine to open an investigation of former Vice President Joe Biden, a leading contender for the Democratic nomination for the 2020 election.
"It's the first time I heard it", he said.
Yovanovitch's testimony is the second public hearing of the inquiry.
The inquiry threatens Trump's presidency even as he seeks re-election in November 2020.
Pelosi's comments could offer a preview of articles of impeachment Democrats might put forward. Trump also asked Zelenskiy to investigate a debunked conspiracy theory embraced by some Trump allies that Ukraine, not Russian Federation, interfered in the 2016 US election.
It's also spelled out in the Constitution as one of the possible grounds for impeachment - "treason, bribery or other and high crimes and misdemeanours". Democrats have begun to use the words bribery or attempted bribery in discussing Trump's actions. According to precedent, obstruction could be another article of impeachment.
"Quid pro quo: Bribery", Pelosi said about Trump's July 25 phone call in which he asked Ukrainian President Volodymyr Zelensky for a favour.
In an interview with CNN, on Thursday, Nov. 14, Clinton said President Trump should leave the impeachment fight to his staff and focus on his agenda. But in 1974, Richard Nixon resigned in the face of certain impeachment and removal from office for the Watergate scandal. Pelosi said Trump's actions to enlist a foreign power to help him in a U.S. election and the obstruction of information about that - she called it a cover-up - "makes what Nixon did look nearly small". House Republican leader Kevin McCarthy accused Schiff of lying at Wednesday's hearing about not knowing the identity of the whistleblower within the United States intelligence community whose complaint about Trump's call triggered the impeachment inquiry.
What we saw on display Wednesday were two dedicated, experienced career foreign policy officials who had been desperately trying to figure out what the president wanted - and inferring his intentions based on snippets of information from others.
While Trump applauded the aggressive stance of some of his Republican defenders, he felt that numerous lawmakers in the opening hearing could have done more to support him and he pressed that case with congressional allies ahead of Friday, according to Republicans who were not authorized to speak publicly about private conversations and were granted anonymity.
The president, who said he was too busy to watch the initial hearing as it was televised, caught up in the White House residence Wednesday evening and tweeted along with a Fox News morning recap Thursday. Trump's personal lawyer, Rudy Giuliani, was working at the time to persuade Ukraine to carry out the two investigations.
At a private dinner for big donors with Trump at the Trump Hotel in Washington in 2018, Parnas told the president that Yovanovitch was unfriendly to Trump and his interests, the Washington Post reported on Tuesday citing unnamed people familiar with the event.
Following the call, the staff member asked Mr Sondland, the US Ambassador to the European Union, what Mr Trump thought about Ukraine, said Mr Taylor, who is the top US diplomat in Ukraine.