President Trump blasted House Speaker Nancy Pelosi and Democratic California Rep. Adam Schiff, urging both to appear as witnesses in his Senate impeachment trial.

"Why did Nervous Nancy allow corrupt politician Shifty Schiff to lie before Congress?" asked Trump on Twitter Sunday. "He must be a Witness, and so should she!"

Why did Nervous Nancy allow corrupt politician Shifty Schiff to lie before Congress? He must be a Witness, and so should she! — Donald J. Trump (@realDonaldTrump) January 12, 2020

The same morning, Pelosi, 79, accused the president of being in "complete denial about Russia's role" in election meddling during an interview with This Week's George Stephanopoulos amid reports that the United States is probing whether the Kremlin is targeting 2020 Democratic front-runner former Vice President Joe Biden. She also suggested that she has doubts about Senate Majority Leader Mitch McConnell's relationship with Russia and that, with Trump, "all roads lead to Putin."

Pelosi has yet to send the two articles of impeachment against Trump that the House of Representatives passed on Dec. 13. The California Democrat claims she will send them "soon" but wants assurances from McConnell that the trial will be fair.

House Intelligence Committee Chairman Schiff headed the House's investigation into Trump's July 25 phone call with Ukrainian President Volodymyr Zelensky. Trump called Schiff a "deranged human being" after he read a parody version of the transcript between Zelensky and Trump.