House Speaker Nancy Pelosi, D-Calif., knocked President Trump's behavior, suggesting he wasn't "presidential" when he called her "Crazy Nancy" during a news conference on Thursday.

"When the 'extremely stable genius' starts acting more presidential, I’ll be happy to work with him on infrastructure, trade and other issues," she tweeted in response to a quote from Trump.

Trump, during his news conference on Thursday, claimed that Pelosi had "lost it." "She's not the same person. She's lost it.… She is a mess," he said.

TRUMP CALLS OUT PELOSI FOR ACCUSING HIM OF A 'COVER-UP' DURING INFRASTRUCTURE MEETING

Trump, Pelosi, and Senate Minority Leader Chuck Schumer, D-N.Y., met on Wednesday but the meeting was cut short. Trump left the meeting, declaring that he wouldn't work with Democrats on infrastructure until they dropped investigations into his administration.

At her weekly news conference on Thursday, Pelosi claimed that Trump had a "temper tantrum" and suggested his associates stage an "intervention." Trump tried to set the record straight on Thursday by asking his advisors to testify to his "calm" demeanor during the meeting.

Trump has refused to comply with congressional subpoenas while Democrats have continued pressing for more information following Special Counsel Robert Mueller's report.

KELLYANNE CONWAY, NANCY PELOSI CLASH AFTER TRUMP MEETING WITH DEMOCRATS WAS CUT SHORT

On Twitter, the president defended himself as "extremely calm" and blasted Democrats for continuing to pursue the Russia investigation.

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"When the Democrats in Congress refinish, for the 5th time, their Fake work on their very disappointing Mueller Report finding, they will have the time to get the REAL work of the people done. Move quickly!" he exclaimed.

Fox News' Frank Miles and the Associated Press contributed to this report.