'This is what is called a "fact"': Top congressman slams Trump ahead of Russia hearing

The ranking Democratic congressman on the House Intelligence Committee hit back at President Donald Trump's claim that hearings into his campaign's ties to Russia were "FAKE NEWS."

"Mr. President, the Russians hacked our election and interfered. No one disputes this now, but you. This is what is called 'fact,'" Rep. Adam Schiff (D-CA) tweeted in response to Trump.

Schiff also chided the president for unfounded claims that former President Barack Obama tapped the phones at Trump Tower, as well as White House statements that had "collateral damage" with US allies Britain and Germany.

Schiff defended the continued investigation into ties between Trump's campaign and Russian operatives to NBC's Chuck Todd on Sunday.

"There is circumstantial evidence of collusion," Schiff told Todd on "Meet the Press."

"There is direct evidence, I think, of deception and that's where we begin the investigation."

FBI Director James Comey and National Security Agency Director Adm. Mike Rogers are set to publicly testify Monday about their investigations into possible links between Russia and Trump's campaign, as part of the House Intelligence Committee's investigation into allegations that Russia meddled in US elections.

"James Clapper and others stated that there is no evidence Potus colluded with Russia," Trump tweeted Monday morning. "This story is FAKE NEWS and everyone knows it!"

In follow-up tweets, the president claimed Democrats "made up and pushed the Russian story" to explain Democratic nominee Hillary Clinton's loss in the presidential election, and called on Congress and the US intelligence community to look into classified-information leaks.

Here are Schiff's tweets from Monday morning:

Sonam Sheth contributed reporting to this story.