President Donald Trump said "I don't do cover-ups" at a surprise White House press conference where he blasted congressional Democratic investigations into his presidency and the suggestions that he should be impeached.

Trump's angry, wide-ranging denunciations of the probes came after he walked out of meeting at the White House with congressional leaders that was supposed to talk about efforts to improve the nation's infrastructure. At that meeting, Trump complained about those investigations.

The president's ostensibly impromptu press conference stunned members of the media at the White House, who had no advance notice of it, and who were expecting to be reporting details of the infrastructure meeting.

"This whole thing was a take-down attempt at the president of the United States," Trump told reporters, referring to special counsel Robert Mueller's probe of Russian interference in the 2016 election, possible collusion by members of the Trump campaign, and possible obstruction of justice by Trump himself.

He also said that the press should be "ashamed" of themselves for how they have reported on Mueller's investigation

"Get these phony investigations over with," Trump said, referring to multiple inquiries by congressional Democrats into still-sealed details of the Mueller investigation and other issues involving the president.

"Here's the bottom line: There was no collusion, there was no obstruction," the president said. "The crime was committed on the other side."

"I don't speak to Russians about campaigns," Trump said. "It's a hoax. The greatest hoax in history."

Trump repeatedly used the phrase "the 'I' word" during the press conference, referring to calls by an increasing number of Democrats to launch an impeachment inquiry in the House of Representatives.

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