WASHINGTON (CNN) -- The Department of Justice is under pressure to provide any documents related to President Donald Trump's accusation -- presented so far without evidence -- that the Obama administration wiretapped his phones at Trump Tower during the campaign.
The House Intelligence Committee has set a Monday deadline for the DOJ to provide the evidence, a source familiar with the matter has told CNN, and has sent letters throughout the intelligence community this week to obtain records related to Russia.
Former President Barack Obama has denied the allegations through a spokesman, and his former director of national intelligence, James Clapper, also has publicly refuted them. Sources have told CNN that FBI Director James Comey also pushed back against Trump's claim.
Trump has not publicly provided any evidence for his allegations, first made more than a week ago. Sunday night, Kellyanne Conway, a top adviser to the President, appeared to expand the allegations by suggesting to the Bergen Record there could have been even wider spying of the Trump campaign, including the use of microwaves and television sets. Like the President, however, she did not provide any evidence, and later said she was speaking generally about surveillance.
As Congress' deadline looms, calls for Trump to produce evidence have grown louder, including by some in his own party.
"The President has one of two choices: either retract or provide the information that the American people deserve," Sen. John McCain told CNN's Jake Tapper Sunday on "State of the Union." "I have no reason to believe that the charge is true, but I also believe that the President of the United States could clear this up in a minute."
Two congressmen privy to sensitive intelligence information said this weekend that they, too, had no information currently to support Trump's claims.
The House Intelligence Committee's top Democrat, Rep. Adam Schiff, said on ABC's "This Week": "I don't expect we'll see evidence of this."
And House Speaker Paul Ryan, asked directly on CBS News' "Face the Nation" if he had seen evidence of the wiretaps, said: "No."
Conway said Sunday that "surveillance" could go beyond the tapping of phones.
"What I can say is there are many ways to surveil each other," Conway told the Record. "You can surveil someone through their phones, certainly through their television sets --- any number of ways."
She went on to allege that the spying could have been done with "microwaves that turn into cameras," adding: "We know this is a fact of modern life."
Conway also reiterated Trump's request that an investigation into the wiretapping claims be included into a congressional investigation into Russia's alleged meddling in the 2016 election.
Pressed on ABC's "Good Morning America" Monday morning about her comments to the Record, Conway said she was speaking about "surveilling generally" and "wasn't making a suggestion about Trump Tower."
"I have no evidence," Conway said, "but that's why there is an investigation in Congress."
She later tweeted that the Record's headline -- "Kellyanne Conway suggests even wider surveillance of Trump campaign" -- was "just wrong."
"Response to Bergen Record was about surveillance articles in news & techniques generally, not about campaign. Headline just wrong," Conway said.
This story has been updated.
CNN's Eli Watkins and David Wright contributed to this report.
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