Senior US lawmakers say they have seen no evidence to support President Donald Trump's claim that his predecessor Barack Obama wiretapped his New York home and office building.
"We don't have any evidence that that took place," Devin Nunes, the Republican head of the congressional committee looking into the allegation, said at a press conference Wednesday.
"I don't think there was an actual tap of Trump Tower," said Nunes, whose House Intelligence Committee is also investigating suspected Russian interference in last year's US presidential election.
Nunes's conclusion was echoed by the panel's top Democrat, Adam Schiff.
"To date I've seen no evidence that supports the claim that President Trump made that his predecessor had wiretapped he and his associates at Trump Tower," Schiff said at the press conference.
"Thus far, we have seen no basis for that whatsoever."
On March 4, Trump sparked a furor when he wrote on his Twitter account that Obama had put a wiretap on communications at Trump Tower, the New York home of the president and first family, before the November 8 election.
"Terrible! Just found out that Obama had my 'wires tapped' in Trump Tower just before the victory. Nothing found. This is McCarthyism!"
"Is it legal for a sitting President to be 'wire tapping' a race for president prior to an election? Turned down by court earlier. A NEW LOW!" he wrote in a second tweet.
- Trump: words were 'in quotes' -
The tweets set off a fierce controversy, in part because it was unprecedented for a US president to accuse a predecessor of a felony crime.
The allegation was also remarkable because Trump -- known for making bombastic and often unsubstantiated claims on Twitter -- would have access to secret law enforcement and intelligence inquiries containing such information.
In an interview late Wednesday with Fox News, Trump was asked how he found out about the alleged wiretapping.
"I had been reading about things," he said, before making a reference to a New York Times article from January 20 and "other things" that he read where wiretapping was discussed.
Trump also mentioned by name a Fox News reporter who "the day previous" - presumably March 3 - "was talking about certain, very complex sets of things happening. And wiretapping. I said 'wait a minute, there's lot of wiretapping being talked about.' I'd been seeing a lot of things."
Trump told Fox "don't forget: when I say wiretap, those words were in quotes... because wiretapping is pretty old-fashioned stuff. But that really covers surveillance and many other things."
He added, however, that "for the most part I'm not going to discuss it because... we will be submitting things before the committee very soon that hasn't been submitted as of yet."
- FBI chief to testify -
During the press conference with Nunes and Schiff, they said they did not expect to hear evidence backing up Trump's claim when James Comey, director of the Federal Bureau of Investigation, testifies to the House Intelligence Committee on Monday.
But the two congressmen said they were hoping to make progress on the issues of Russia's interference in the 2016 election, including how many people linked to the Trump campaign might have been wiretapped in the course of that or other inquiries.
Also testifying Monday will be Michael Rogers, director of the National Security Agency, the government's electronic spying body.
Another intelligence hearing, with testimony from other witnesses, is scheduled for March 28.