U.S. lawmakers from both parties said on Sunday they had seen no proof to support the claim by Republican President Donald Trump that his predecessor Barack Obama had wiretapped him last year, adding pressure on Trump to explain or back off his repeated assertion.
Several Republicans last week urged Trump to apologize for the allegations he made in a series of tweets on March 4. The maelstrom also caused tension with key U.S. allies and threatens to distract Republicans from campaign promises on health care and taxes.
"I don't know the basis for President Trump's assertion," U.S. Senator Susan Collins, a Republican, said on NBC's "Meet the Press." "I do believe he owes us that explanation."
Collins said she supported Trump as president, but she wouldn't side with him if he "misstated what the facts are."
FBI Director James Comey is expected to be asked about Trump's claims when he testifies at a rare public hearing on Monday about alleged Russian meddling in the 2016 presidential election. Russia has denied the assertion.
Representative Adam Schiff, the top Democrat on the House Intelligence Committee holding the hearing, called Trump's claims "patently false" and said he expected Comey to say as much on Monday.
The White House and Trump allies have sought to focus attention away from the controversies by calling for investigations of leaks to the news media.
Representative Devin Nunes, who leads the House intelligence panel, said leaks to reporters about former Trump national security adviser Michael Flynn were criminal and that his panel was probing whether other names were leaked.
Trump has been dogged by allegations that his associates had ties to Russian officials. He fired Flynn last month after reports he had discussed sanctions with Russia's ambassador before Trump took office, without telling other White House officials.
"The one crime we know that's been committed is that one: the leaking of someone's name," Nunes said on "Fox News Sunday." "Were there any other names that were ... leaked out?"
'Owed an Apology'
Nunes, despite being a Trump ally who served on the president-elect's transition team, has not taken Trump's side on the wiretapping claim. On Fox, he said he did not believe it occurred.
Still, the White House has not backed down. The administration was forced to reassure key ally Britain after White House press secretary Sean Spicer repeated a Fox News analyst's claim that a British intelligence agency helped Obama wiretap Trump. The British government strongly denied it.
The issue led to an awkward moment on Friday at a joint press conference with visiting German Chancellor Angela Merkel when Trump was asked about the wiretap claims by a German reporter.
Trump said he and Merkel had "something in common," apparently referring to reports during the Obama administration that Merkel's phone was bugged. The quip left the German leader looking bewildered.
Senior Republican Representative Tom Cole told reporters on Friday that Trump owed Obama an apology. Representatives Charlie Dent and Will Hurd, also Republicans, made similar comments.
"I see no indication that that's true," Cole said of the wiretapping charge.
Unless Trump produces convincing proof, Cole added, "President Obama is owed an apology."
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