WASHINGTON, March 15 (Reuters) - The House of Representatives Intelligence Committee chairman said on Wednesday he did not believe Trump Tower was tapped during the 2016 presidential campaign, adding pressure to FBI Director James Comey to provide evidence supporting or debunking Republican President Donald Trump's claim.
"We don't have any evidence that that took place," said U.S. Representative Devin Nunes, the Republican chairman of the House of Representatives Intelligence Committee. "I don't think there was an actual tap of Trump Tower."
Trump made the claim on Twitter on March 4 without providing evidence, and representatives of former Democratic President Barack Obama have denied it. A number of congressional committees added the startling accusation to their wider investigations of possible Russian meddling in the election campaign and Russian ties to Trump and his associates.
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The top Democrat on the House Intelligence Committee, Adam Schiff, said Comey would be asked about wiretap evidence at a rare public hearing next Monday. "It deeply concerns me that the president would make such an accusation without basis."
Nunes said if Trump's tweets were taken literally, then "clearly the president was wrong."
U.S. intelligence agencies have concluded that Russia conducted cyber attacks on Democrats in an effort to influence the 2016 U.S. election on Trump's behalf. Russia has denied this.
At the same time, Trump has been dogged by allegations that his advisers or associates had ties to Russian officials. Trump fired his national security adviser, Michael Flynn, last month after he failed to disclose contacts with Russia's ambassador before Trump took office on Jan. 20.
Comey and Admiral Mike Rogers, the head of the National Security Agency, have agreed to testify before the House committee on issues related to Russia's role in the election. Schiff said he expected the Federal Bureau of Investigation to cooperate and was "prepared to support the use of the coercive process" if they did not, referring to the issuing of subpoenas.
In Richmond, Virginia, Attorney General Jeff Sessions told reporters that he never gave Trump any reason to believe he was wiretapped by the previous administration, according to a transcript provided by CBS News.
Later on Wednesday, Comey was expected to brief leaders of the Senate Judiciary Committee about any FBI investigation of Russian election-related activities, according to media reports citing the committee's Republican chairman, Charles Grassley. Grassley had threatened to hold up Trump's nominee for deputy attorney general, Rod Rosenstein, until Comey briefed them.
While White House spokesman Sean Spicer said on Tuesday that Trump was "extremely confident" the Justice Department would produce evidence to support the wiretap assertion, a number of Trump's fellow Republicans in Congress remained unconvinced.
CONGRESS FLEXING MUSCLE
Republican Senator Lindsey Graham and Democratic Senator Sheldon Whitehouse, both Judiciary Committee members, asked Comey two weeks ago to provide information on Russian activities and the wiretapping by Wednesday.
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Graham said he was prepared to issue subpoenas for information on whether the FBI received a warrant to tap Trump Tower.
"Congress is going to flex its muscles," Graham said on CNN.
James Clapper, the director of national intelligence under Obama, has told NBC he knew of no warrant to wiretap Trump Tower. Graham said he had no reason to believe a judge ever issued a warrant, which would have reflected there was probable cause that the Trump campaign was colluding with the Russians.
If it is not true, he said, the FBI should confirm that.
"The longer it takes to answer that question, the more suspicious I get," Graham said on MSNBC.
Congressional Democrats want a special prosecutor or nonpartisan select committee to investigate any Russian ties. But Trump's fellow Republicans, who control majorities in both the Senate and House of Representatives, say the probes by congressional committees are sufficient.
Democratic Senator Tim Kaine, appearing on CNN, said he believed Comey will say the FBI was "looking at" Russia connections to Trump.
"We have to understand everything about the ties between Russia, the Trump campaign, the Trump transition, the Trump administration," said Kaine, a member of the Foreign Relations Committee and Democratic presidential candidate Hillary Clinton's running mate. "Especially the degree to which Russia tried to invade the American election, because we have to protect future elections." (Reporting by Doina Chiacu; Editing by Jeffrey Benkoe and Jonathan Oatis)
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