Boris Johnson on Wednesday refused to deny that a large party was held in No.10 in late December – breaking the regulations.
But there are now new claims that staff repeatedly gathered after work to drink alcohol and play party games in their offices, despite rules banning mixing between household bubbles.
The Daily Mirror newspaper reports that on 18 December around 40 people drank and celebrated late into the night.
Food, party games, and alcohol all said to have been available at the gathering, according to the BBC – whose source described the mood at as “downbeat”.
The party went ahead two days after the government moved London into Tier 3 restrictions, banning all indoor mixing outside household bubbles.
And the day after the bash took place Mr Johnson scrapped plans for a Christmas relaxation of rules, keeping millions from seeing their families.
Another party is said to have taken place on 27 November. This event was reportedly a leaving drinks for special advisor Cleo Watson, who was leaving No.10 to work elsewhere.
Mr Johnson himself is said to have attended the November bash and made a short speech before commenting on how crowded the room was.
The Guardian newspaper also reports a source claiming there were “loads of leaving parties” during both the second and third lockdown.
A No.10 spokesperson refused to deny parties had taken place and said only that rules had been followed.
“Covid rules have been followed at all times,” they said.
But the government has also repeatedly claimed the rules were not broken in other similar cases where ministers and officials have taken liberties – including Matt Hancock's affair and Dominic Cummings' trip to Barnard Castle.
At prime minister’s questions on Wednesday, Keir Starmer accused Mr Johnson of “taking the British public for fools for following the rules".
“The prime minister doesn’t deny there was a Downing Street Christmas party last year," he said.
"He says no rules were broken. Both of those things can’t be true.”
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