The US has made a "formal apology" to Britain over accusations a UK spy agency worked with former President Barack Obama to wiretap Trump Tower, according to The Telegraph.

White House press secretary Sean Spicer claimed in a briefing on Thursday that Obama partnered with the UK's Government Communications Headquarters (GCHQ) for an operation spying on Trump Tower during the presidential campaign.

The Telegraph reports that both Spicer and National Security Adviser H.R. McMaster apologized to Britain.

"The apology came direct from them," an intelligence source told the British newspaper.

McMaster reportedly apologized directly to Prime Minister Theresa May's security chief Sir Mark Lyall Grant, according to The Sun.

RELATED: Donald Trump, Theresa May hold joint press conference

17 PHOTOS Donald Trump, Theresa May meet at White House See Gallery Donald Trump, Theresa May meet at White House WASHINGTON, DC - JANUARY 27: British Prime Minister Theresa May and U.S. President Donald Trump walk along The Colonnade of the West Wing at The White House on January 27, 2017 in Washington, DC. British Prime Minister Theresa May is on a two-day visit to the United States and will be the first world leader to meet with President Donald Trump. (Photo by Christopher Furlong/Getty Images) WASHINGTON, DC - JANUARY 27: British Prime Minister Theresa May and U.S. President Donald Trump walk along The Colonnade of the West Wing at The White House on January 27, 2017 in Washington, DC. British Prime Minister Theresa May is on a two-day visit to the United States and will be the first world leader to meet with President Donald Trump. (Photo by Christopher Furlong/Getty Images) WASHINGTON, DC - JANUARY 27: British Prime Minister Theresa May with U.S. President Donald Trump walk along The Colonnade at The White House on January 27, 2017 in Washington, DC. British Prime Minister Theresa May is on a two-day visit to the United States and will be the first world leader to meet with President Donald Trump. (Photo by Christopher Furlong/Getty Images) U.S. President Donald Trump escorts British Prime Minister Theresa May after their meeting at the White House in Washington, U.S., January 27, 2017. REUTERS/Kevin Lamarque British Prime Minister Theresa May and U.S. President Donald Trump participate in a joint news conference at the White House in Washington, U.S., January 27, 2017. REUTERS/Carlos Barria WASHINGTON, DC - JANUARY 27: U.S. President Donald Trump (R) and British Prime Minister Theresa May (L) participate in a joint press conference in the East Room of the White House January 27, 2017 in Washington, DC. Prime Minister May is on a visit to the White House and had a bilateral meeting in the Oval Office with President Trump. (Photo by Alex Wong/Getty Images) WASHINGTON, DC - JANUARY 27: U.S. President Donald Trump (R) and British Prime Minister Theresa May (L) participate in a joint press conference in the East Room of the White House January 27, 2017 in Washington, DC. Prime Minister May is on a visit to the White House and had a bilateral meeting in the Oval Office with President Trump. (Photo by Alex Wong/Getty Images) WASHINGTON, DC - JANUARY 27: U.S. President Donald Trump (R) and British Prime Minister Theresa May ,participate in a joint press conference at the East Room of the White House January 27, 2017 in Washington, DC. Prime Minister May is on a visit to the White House and had a bilateral meeting in the Oval Office with President Trump. (Photo by Mark Wilson/Getty Images) WASHINGTON, DC - JANUARY 27: U.S. President Donald Trump speaks during a joint press conference with British Prime Minister Theresa May in the East Room of the White House January 27, 2017 in Washington, DC. Prime Minister May is on a visit to the White House and had a bilateral meeting in the Oval Office with President Trump. (Photo by Alex Wong/Getty Images) WASHINGTON, DC - JANUARY 27: U.S. President Donald Trump (R) and British Prime Minister Theresa May ,participate in a joint press conference at the East Room of the White House January 27, 2017 in Washington, DC. Prime Minister May is on a visit to the White House and had a bilateral meeting in the Oval Office with President Trump. (Photo by Mark Wilson/Getty Images) U.S. President Donald Trump meets with British Prime Minister Theresa May in the White House Oval Office in Washington, U.S., January 27, 2017. REUTERS/Kevin Lamarque British Prime Minister Theresa May (L) and US President Donald Trump shake hands beside a bust of former British Prime Minister Winston Churchill in the Oval Office of the White House on January 27, 2017 in Washington, DC. / AFP / Brendan Smialowski (Photo credit should read BRENDAN SMIALOWSKI/AFP/Getty Images) WASHINGTON, DC - JANUARY 27: British Prime Minister Theresa May with U.S. President Donald Trump in The Oval Office at The White House on January 27, 2017 in Washington, DC. British Prime Minister Theresa May is on a two-day visit to the United States and will be the first world leader to meet with President Donald Trump. (Photo by Christopher Furlong/Getty Images) British Prime Minister Theresa May (L) and US President Donald speak in the Oval Office of the White House on January 27, 2017 in Washington, DC. / AFP / Brendan Smialowski (Photo credit should read BRENDAN SMIALOWSKI/AFP/Getty Images) US President Donald Trump listens while British Prime Minister Theresa May speaks during a press conference at the White House January 27, 2017 in Washington, DC. / AFP / Brendan Smialowski (Photo credit should read BRENDAN SMIALOWSKI/AFP/Getty Images) WASHINGTON, DC - JANUARY 27: British Prime Minister Theresa May with U.S. President Donald Trump in The Oval Office at The White House on January 27, 2017 in Washington, DC. British Prime Minister Theresa May is on a two-day visit to the United States and will be the first world leader to meet with President Donald Trump. (Photo by Christopher Furlong/Getty Images) Theresa May, U.K. prime minister, smiles during a joint news conference with U.S. President Donald Trump, not pictured, in the East Room of the White House in Washington, D.C., U.S., on Friday, Jan. 27, 2017. The British prime minister is planning to pitch a free-trade deal to the new U.S. leader just as the reality of a new era of protection for American workers sinks in. Photographer: Andrew Harrer/Bloomberg via Getty Images Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

"General McMaster also reassured No10 that the White House would never repeat the embarrassment, which threatened to put crucial Trans-Atlantic intelligence cooperation at risk," The Sun reports.

During a White House press briefing on Thursday, Spicer cited comments from Fox News commentator Andrew Napolitano that Spicer said confirmed GCHQ took part in a spy operation at Trump Tower during the 2016 US election.

"Three intelligence sources have informed Fox News that President Obama went outside the chain of command," Spicer said, reading from notes in the White House press room on Thursday.

"[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, what is that? It's the initials for the British Intelligence Spying Agency," Spicer said.

A spokesperson for the GCHQ quickly issued a statement debunking the Fox News report Spicer was referencing.

"Recent allegations made by media commentator judge Andrew Napolitano about GCHQ being asked to conduct 'wiretapping' against the then president-elect are nonsense," the statement read. "They are utterly ridiculous and should be ignored."

NOW WATCH: 'F--- you for that': Milo Yiannopoulos attacks the media in a press conference after resigning from Breitbart

See Also: