(Bloomberg) -- Pressure mounted on U.K. Prime Minister Boris Johnson after a video emerged showing key aides joking about a party in Downing Street last Christmas at a time when such gatherings were banned.

The video, obtained by ITV News and which ITV said was recorded four days after the alleged event, shows Johnson’s then press secretary Allegra Stratton rehearsing for a TV media briefing and saying there was “definitely no social distancing” when asked about a party. 

A backlash has been growing over whether Johnson’s own officials held a party in Downing Street last year in breach of the government’s own coronavirus rules, and the episode has cast further doubt over the integrity of Johnson’s administration after a rocky period.

Johnson Faces U.K. Ethics Row Over Covid Rules, Tory Probes (1)

Johnson and his office have refused to deny a party took place, while maintaining that the rules in place at the time were obeyed.

“I have satisfied myself that the guidelines were followed at all times,” Johnson told broadcasters earlier Tuesday when asked about the alleged party.

Pandemic rules in place at the time stated: “Although there are exemptions for work purposes, you must not have a work Christmas lunch or party, where that is a primarily social activity.”

The Daily Mirror newspaper reported last month that Johnson’s team held a party Dec. 18 with about 40 to 50 people “cheek by jowl,” citing people familiar with the matter it didn’t identify.

It wasn’t clear from the footage whether the aides were discussing an actual party, or a fictional one for the purposes of the rehearsal.

‘Cheese and Wine’

In the video obtained by ITV, Downing Street aide Ed Oldfield is heard to ask: “I’ve just seen reports on Twitter that there was a Downing Street Christmas party on Friday night, do you recognize those reports?”

Stratton visibly struggles to respond, before saying: “What’s the answer?”

One aide is heard to say: “It wasn’t a party, it was cheese and wine.” Stratton says: “Is cheese and wine alright?”

Through laughter, she finally says: “This fictional party was a business meeting and it was not socially distanced.”

Stratton and Oldfield did not immediately respond to requests for comment from Bloomberg News.

Keir Starmer, leader of the main opposition Labour Party, said the government’s actions were “shameful” at a time when the rules separated people from their families.

“The Prime Minister now needs to come clean, and apologize,” he said. “It cannot be one rule for the Conservatives and another for everyone else.”

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