Britain's top intelligence agency says the United States has agreed to drop its claim that the United Kingdom helped President Barack Obama wiretap Donald Trump – an allegation made by White House Press Secretary Sean Spicer - the BBC, The Times of London and The Guardian reported Friday.

And London's Telegraph newspaper says the U.S. has made a formal apology to the Government Communications Headquarters (GCHQ) and told British Prime Minister Theresa May the allegation will never be repeated.

Though a spokesman for May would not confirm that a formal apology had been made, The New York Times reported that Spicer did reach out to Britain ambassador Kim Derroch to smooth things over.

The reported apology came after GCHQ issued a rare public statement denying the wiretap charges as "nonsense" and "utterly ridiculous."

The uproar started after comments made Thursday by Spicer, who repeated claims from a Fox News report that Obama used GCHQ to spy on Trump so there would be "no American fingerprints on this."

Spicer cited Andrew Napolitano, a former New Jersey Superior Court Judge and Fox judicial analyst, who stated earlier this week that Obama "didn’t use the NSA, he didn’t use the CIA, he didn't use the FBI and he didn't use the Department of Justice - he used GCHQ."

Napolitano also said in his claim that two people went to the GCHQ on Obama's behalf.

"President Obama needs transcripts of conversations involving candidate Trump, conversations involving President-elect Trump, he's able to get it," Napolitano said.

Napolitano repeated the claim Thursday.

Trump has been under fire for claiming in a series tweets that Obama bugged Trump Tower, his gold-colored skyscraper on New York City’s posh Fifth Avenue -- although top U.S. intelligence officials have strenuously denied it happened.

In a statement, the usually-silent GCHQ said: "Recent allegations made by media commentator Judge Andrew Napolitano about GCHQ being asked to conduct 'wiretapping' against the then president-elect are nonsense. They are utterly ridiculous and should be ignored."

Intelligence sources told The Telegraph that Spicer and National Security Adviser H.R. McMaster, both apologized for the gaffe.

Napolitano's allegation drew swift condemnation from Britain soon after it was made. Late Thursday, a UK government spokesman told Newsmax "no part of this story is true."