"Every single day the president is making the case" and "he's becoming self-impeachable," Pelosi said in an interview with the Washington Post, when asked about the possibility of the Republican president being impeached by the House.
Trump on Wednesday asserted executive privilege over Special Counsel Robert Mueller's report on Russian meddling in the 2016 campaign and its underlying investigative materials, escalating the battle with the Democrats on the U.S. House Judiciary Committee.
The move came shortly before the House Judiciary Committee was to vote to hold Attorney General William Barr in contempt for defying a congressional subpoena to hand over the full unredacted report.
The Judiciary Committee is one of number of committees in the Democratic-controlled House that are investigating Trump and his administration on multiple fronts, including White House security clearances and Trump's personal and business dealings.
The House and Senate still are investigating Russian election meddling and possible obstruction of justice by Trump.
Mueller's report cited extensive contacts between Trump's 2016 campaign and Moscow but did not find a conspiracy between Moscow and the campaign. It also described actions that Trump took to try to impede the investigation and congressional Democrats have vowed to continue their own probe into the issue.
Trump has denied any wrongdoing and vowed to fight all congressional subpoenas.
U.S. Attorney General William Barr faces a contempt citation by the House Judiciary Committee on Wednesday for failing to comply with lawmakers' requests, while former White House lawyer Don McGahn faces a similar threat.
U.S. Treasury Secretary Steven Mnuchin also has defied Congress, this week not acting on the House Ways and Means Committee's request for Trump's tax returns.
Republicans, who control the U.S. Senate, have dismissed House Democrats' investigations as political posturing ahead of the 2020 presidential election.
Democrats are divided over how far to take their investigations with some calling for impeachment proceedings and others backing continued panel investigations."The president ... wants to goad us unto impeachment," Pelosi told the Post. Such proceedings would also be "divisive" for the country, she said.