They also have asked the Federal Bureau of Investigation and the Justice Department to produce any information that supports Trump's unsubstantiated claim that his predecessor wiretapped him during the 2016 campaign.
U.S. Republican congressional leaders have refused Democrats' calls for a special prosecutor or select committee to investigate possible links between President Donald Trump's campaign and Russian Federation, saying investigations by congressional committees are sufficient. The aide said Spicer is wrong.
FBI Director James Comey will testify before the House Intelligence Committee today, alongside National Security Agency Director Admiral Michael Rogers, at a hearing about Russian interference in the 2016 election.
The breadth of the probe also includes looking into whether Trump or any of his associates had any connections to the Kremlin and what federal agencies unmasked names of USA citizens who were picked up via incidental collection of surveillance.
However, Speaker Paul Ryan also said Thursday that he believed the claims were false, telling CNN in a news conference that the intelligence committees in the House and Senate "got to the bottom - at least so far with respect to our intelligence community - that no such wiretap existed".
A spokesman for Britain's prime minister says the White House has promised that it won't repeat a claim that United Kingdom spies snooped on U.S. President Donald Trump.
Mr Spicer also chastised the media for focusing so much attention on comments disparaging MrTrump's claim about surveillance.
Reuters reported earlier this week that an unidentified British security official had denied the allegations about Trump.
Nicola Sturgeon to warn PM against blocking second independence vote
In Edinburgh, Nicola Sturgeon said she would be "up for" a discussion with May about the timing of a new independence referendum. Even so, May insisted that Britain's best days lie ahead, after the country has left the EU.
The Russian government has rejected an accusation by USA intelligence agencies that it worked to influence the election in Mr Trump's favour by hacking computer systems, among other methods.
This week, the top four lawmakers in Congress dealing with intelligence issues, Republicans and Democrats, all said that they have been given no evidence to support Trump's allegations.
How low has President Obama gone to tapp my phones during the very sacred election process. "This is Nixon/Watergate. Bad (or sick) guy!", Trump wrote.
The Republican and Democratic heads of the powerful Senate Intelligence committee have put out a statement saying they see "no indication" that Trump Tower was hacked, yet one more indication that President Donald Trump's explosive charge that President Barack Obama had his campaign wiretapped during the 2016 Presidential election season was (ahem) fact challenged.
"As I told you last week about the issue with the president talking about tapping Trump Tower, that evidence still remains the same, that we don't have any evidence that that took place", Nunes told reporters.
Despite agreeing there was "no physical wiretap" at Trump Tower Nunes said it was unclear what other surveillance evidence there might be on Trump or any of his associates.
"I had been reading about things" that mentioned wiretapping, he said.
Trump said there would be "some very interesting items coming to the forefront over the next two weeks".