The New York Times reported on Sunday that FBI Director James Comey asked the Justice Department this weekend to reject Trump's wiretapping claim because it was false and must be corrected, but the department had not done so. The report cited senior U.S. officials.
The White House asked Congress, controlled by Trump's fellow Republicans, to examine whether the Obama administration abused its investigative authority during the 2016 U.S. presidential campaign, as part of an ongoing congressional probe into Russia's influence on the election.
Trump on Saturday alleged, without offering supporting evidence, that Obama ordered a wiretap of the phones at Trump's campaign headquarters in Trump Tower in New York.
"There was no such wiretap activity mounted against the president-elect at the time, or as a candidate or against his campaign," former Director of National Intelligence James Clapper, who left his post at the end of Obama's term in office in January, said on NBC's "Meet the Press."
Under U.S. law, a federal court would have to have found probable cause that the target of the surveillance is an "agent of a foreign power" in order to approve a warrant authorizing electronic surveillance of Trump Tower.
Asked whether there was such a court order, Clapper said, "I can deny it."
Democrats accused Trump of trying to distract from the rising controversy about possible ties to Russia.