Top White House aides apologized to the U.K. government for repeating claims that its intelligence service helped spy on President Donald Trump before his election, said a senior British official, as the administration tried to stop a domestic row contaminating a vital international alliance.

The expressions of regret came in private phone conversations after White House press secretary Sean Spicer on Thursday cited a disputed Fox News commentator’s report suggesting the U.K. helped former President Barack Obama spy on his successor. Spicer was attempting to bolster Trump’s unsubstantiated Twitter claims that he had been wiretapped by the previous administration, but the claim prompted a high-level complaint from the U.K. government.

Kim Darroch, U.K. ambassador to the U.S., and Mark Lyall Grant, May’s national security advisor, expressed their concerns to Spicer and Trump national security advisor H.R. McMaster, a White House official said. Spicer and McMaster told them the press secretary was simply highlighting public reports, not endorsing any specific story, according to the official, who wasn’t authorized to speak on the record.

May’s office declined to comment on whether Trump’s aides had apologized.

Moving On

The White House official didn’t characterize the conversation, but speaking on condition of anonymity, a senior British official said the Trump administration had privately admitted Spicer was wrong about the allegations and apologized for the incident. U.K. Prime Minister Theresa May’s team is keen to move on from the embarrassing row and regard the matter as closed, the official said.

“We have received assurances that these allegations won’t be repeated,” James Slack, a spokesman for May, said Friday. He said allegations that British intelligence had aided Obama in an off-the-books espionage effort were “utterly ridiculous and should be ignored.”

May is hoping to strengthen the transatlantic bond with Trump as she prepares to take the U.K. out of the European Union. British and US officials have begun laying the ground for a new trade deal between the two old allies, which would come into force when the U.K. exits the EU.

Andrew Napolitano, a legal pundit for Fox News who has advised Trump, claimed during a March 14 broadcast that three intelligence sources told the network Obama personally appealed to the British Government Communications Headquarters, known as the GCHQ, to spy on Trump. Spicer highlighted the report in a list of media accounts he read to reporters during his briefing on Thursday, arguing that the stories helped validate Trump’s allegation.

British officials have categorically denied Napolitano’s reporting, and Spicer’s decision to cite it from the White House podium threatened to strain relations between the transatlantic allies. 

Susan Rice, Obama’s national security advisor, said on Twitter Friday that “the cost of falsely blaming our closely ally for something this consequential cannot be overstated. And from the PODIUM.”

One U.S. official familiar with the discussions said the British complained to the Trump administration about Spicer giving a platform to Napolitano’s remarks.

After Spicer’s briefing on Thursday, the GCHQ issued a rare statement flatly dismissing the Fox pundit’s reporting.

“Recent allegations made by media commentator Judge Andrew Napolitano about GCHQ being asked to conduct ‘wire tapping’ against the then President Elect are nonsense,” the agency said in the statement.

Five Eyes

Under the Five Eyes agreement between Australia, Canada, New Zealand, the U.K. and the U.S., allies cannot use each others’ intelligence capabilities to circumvent their own laws, Slack said.

Dominic Grieve, the senior British lawmaker in charge of parliamentary oversight of U.K. state intelligence agencies, said it was “inconceivable” that Britain’s GCHQ listening station could have been asked to “wire tap.”

Trump has riled relations with other allies since taking office on Jan. 20, including Australia, Mexico, and Germany. He’s meeting Friday at the White House with German Chancellor Angela Merkel, their first face-to-face encounter. May was the first foreign leader to meet with Trump after his inauguration.

Thursday’s dispute punctured a traditional day of unity between the U.S. and U.K., with British diplomats among the attendees at St. Patrick’s Day celebrations on Capitol Hill and at the White House. Darroch was at a lunch at the Capitol also attended by the president and Irish Taoiseach Enda Kenny, just hours before Spicer’s briefing.

‘No Indications’

Spicer quoted Napolitano’s comments as part of a lengthy citation of media reports made in response to questions from reporters about a statement from the top Republican and Democrat on the Senate Intelligence Committee. Both said they hadn’t seen any evidence to back up the Trump’s allegations that Obama had spied on him.

“Based on the information available to us, we see no indications that Trump Tower was the subject of surveillance by any element of the United States government either before or after Election Day 2016,” said the panel’s chairman, Richard Burr of North Carolina, and vice chairman, Mark Warner of Virginia.

The White House has said that Trump’s initial claims, posted in a flurry of tweets earlier this month, shouldn’t be taken literally. Officials have said Trump didn’t necessarily mean Obama personally ordered the surveillance; that wiretapping could refer to a broad range of surveillance efforts; and that the effort may not have specifically targeted Trump Tower in New York.

Hearing Scheduled

Trump has so far refused to fully detail what evidence he’s seen to support his allegation. In an interview with Fox News on Wednesday, Trump said he had based his tweets at least partially on media reports, but could release additional information to support his claims.

A spokesman for Obama has denied that he personally ordered surveillance against Trump.

Trump’s allegations are expected to dominate a House Intelligence Committee hearing on Monday with Federal Bureau of Investigation Director James Comey and National Security Agency Director Mike Rogers. The Justice Department also faces a deadline that day to turn over any evidence that the Obama administration may have put Trump under surveillance.