Hours before the House Intelligence Committee opens hearings on Monday, President Trump denounced accusations that he and associates had some kind of relationship with Russians involved in hacking Democratic officials during last year's election.

"(Former national intelligence director) James Clapper and others stated that there is no evidence Potus colluded with Russia," Trump tweeted. "This story is FAKE NEWS and everyone knows it!"

The president added: "The Democrats made up and pushed the Russian story as an excuse for running a terrible campaign. Big advantage in Electoral College & lost!"

The House Intelligence Committee is also looking into Trump's accusation that predecessor Barack Obama had him wiretapped during last year's election — a claim for which committee leaders say there is no evidence.

FBI Director James Comey is expected to repudiate Trump's wiretapping claim about Obama in testimony before the House Intelligence Committee on Monday.

Comey, who privately encouraged Justice Department officials to refute Trump's accusations soon after he made then in a March 4 tweet storm, is scheduled to testify along with National Security Agency Director Mike Rogers.

Trump, meanwhile, has complained about news leaks, and said that is what the committee should be looking into. "The real story that Congress, the FBI and all others should be looking into is the leaking of Classified information," Trump tweeted. "Must find leaker now!"

The wiretapping charges brought furious denials from Obama aides — who pointed out that the law forbids presidents from ordering wiretaps — to a diplomatic flap with the United Kingdom, which protested claims by Trump allies that British allies may have been involved in the wiretapping.

Despite a rising number of officials who say there is no evidence, Trump and aides have not backed down from the Obama wiretapping claim. They have often sought to buttress their case by citing news reports, many of them based on anonymous sources.

During a Friday news conference with German Chancellor Angela Merkel — whose phones had been tapped by the Obama administration — Trump told his guest: "As far as wiretapping, I guess by this past administration, at least we have something in common, perhaps."

The accusation also triggered the diplomatic row with another ally, as Trump and aides cited a report by Fox News commentator Andrew Napolitano that Obama asked a British intelligence agency to tap Trump. The British government objected and the Trump administration pledged not to use the claim again. Asked about the flap, Trump said: "That was a statement made by a very talented lawyer on Fox, and so you shouldn't be talking to me, you should be talking to Fox. OK?"