The chairman of the US House of Representatives Intelligence Committee, Republican Devin Nunes, has said that there "never was" evidence that former president Barack Obama ordered a wiretap of President Donald Trump and Trump Tower during the last presidential campaign.

"If you take the president literally, it didn't happen," Nunes told the Fox on Sunday show.

His committee requested evidence of the wiretapping by Friday but Nunes said that a Justice Department report submitted to the committee did not show any proof to support Trump's claims.

"Was there a physical wiretap of Trump Tower?" Nunes said. "No. There never was."

The committee is set to start public hearings today (Monday 20 March) into allegations that Russia attempted to influence the election and steer the outcome in favour of Trump. That was the conclusion of a report published by US intelligence agencies in January.

Nunes added that there was no Foreign Intelligence Surveillance Act (Fisa) warrant to wiretap Trump Tower that he was aware of.

A Fisa warrant, which permits intelligence agencies to spy on citizens in the US, would be issued in a very secretive environment. Some news organisations including the BBC have reported on a warrant that may have included Trump campaign team members.

The wiretap allegations were given fresh impetus by Trump's press secretary, Sean Spicer, quoting a Fox News report that claimed that GCHQ had tapped Trump Tower at the behest of the Obama administration. In a rare statement, GCHQ said that the accusations were "utterly ridiculous and should be ignored."

Reports then said that Spicer, along with National Security Adviser Herbert McMaster, had quietly apologised to the UK for the claim but the White House later denied that the apology had taken place.