TORY chiefs have admitted to hosting yet another festive bash last year while coronavirus restrictions were in force – intensifying pressure on the embattled Prime Minister. 

Following a day in which political allies, opponents and the public reacted furiously to reports of Christmas parties on Downing Street, the Conservatives admitted an event organised by Shaun Bailey’s mayoral campaign took place in the party’s Westminster headquarters on December 14 – while the capital was in Tier 2 restrictions.

According to the Times, the “raucous” party took place in the HQ’s basement, was attended by No 10 aides and featured dancing and wine-drinking into the early hours despite indoor social mixing being banned at the time.

It follows reports of yet another festive event in December 2020, with No 10 staffers said to have attended a "quiz night".

The further damaging details emerged as Labour urged police to open an investigation into allegations staff broke coronavirus rules at the event in No 10, saying it was “implausible” for Scotland Yard to suggest there is insufficient evidence to investigate.

Allegra Stratton became the first casualty of the affair when she emotionally stood down after video emerged of her and other advisers joking about Covid restrictions just days after the gathering in No 10 on December 18 last year.

But the Prime Minister’s attempt to move on from the row by tasking Cabinet Secretary Simon Case – who may have attended the bash himself – with undertaking an investigation appeared to have failed as details emerged of the separate party.

A Tory spokesman said: “Senior CCHQ [Conservative Campaign Headquarters] staff became aware of an unauthorised social gathering in the basement of Matthew Parker Street organised by the Bailey campaign on the evening of December 14.

“Formal disciplinary action was taken against the four CCHQ staff who were seconded to the Bailey campaign.”

The Metropolitan Police acknowledged it had received “a significant amount of correspondence” relating to the alleged breaches in No 10 in the run up to Christmas last year but said they do not “provide evidence of a breach” of Covid rules.

“Based on the absence of evidence and in line with our policy not to investigate retrospective breaches of such regulations, the Met will not commence an investigation at this time,” it added.

But the force did leave open the possibility of further inquiries by saying it would consider “any evidence” that emerges in the Case inquiry.

Health Secretary Sajid Javid suggested the probe could look beyond the event on December 18.

“I do know that Simon Case is not just looking at a particular date,” Javid said. “He is free to look at whatever dates he wants to consider.”

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Labour’s shadow health secretary West Streeting said the Met should be “knocking on doors, taking statements and investigating people in No 10 in the way they would my constituents or anyone else in the country”.

“It seems implausible for the Metropolitan Police to argue there is no evidence that parties took place,” he told reporters.

“They’ve got to pursue this investigation without fear or favour and treat the Prime Minister and his staff as they would treat anyone else. It can’t be one rule for the Prime Minister and another for everyone else.”

Meanwhile, Downing Street did not comment on a separate report in the Times that Dan Rosenfield, then Johnson’s incoming chief of staff, took part in the December 18 party while London was under Tier 3 restrictions.

The National: Boris Johnson's chief of staff, Dan RosenfieldBoris Johnson's chief of staff, Dan Rosenfield

The Prime Minister has repeatedly insisted the rules were followed that night but apologised over the impression made by leaked footage of No 10 staff joking about Covid restrictions.

It showed Stratton and aides laughing on December 22 about a supposedly “fictional party” having taken place in Downing Street days earlier as she took part in a rehearsal for her subsequently axed role hosting televised press briefings.

She resigned as a Government adviser on Wednesday, saying: “I will regret those remarks for the rest of my days and I offer my profound apologies to all of you at home for them.”

Meanwhile, Johnson was forced to deny allegations, including from senior Conservative William Wragg, that his announcement of further coronavirus restrictions was a “diversionary tactic” from the scandal.

The Prime Minister also appeared to concede that the Cabinet Secretary would be able to go further than just reviewing the events of December 18 and “look at other things”, with other alleged gatherings in Downing Street over the festive period last year.

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Scottish Tory leader Douglas Ross said Johnson should quit if he was found to have misled Parliament.

“If he knew there was a party, if he knew it took place, then he cannot come to the House of Commons and say there was no party,” he told Sky News.

Meanwhile, Nicola Sturgeon urged people to follow Government coronavirus rules “even if you feel angry with a politician just now”.

She explained on social media that policies announced for England were already in place for Scotland, but added: “Tough question we all face in period ahead is whether these protections will be strong enough against a rapidly spreading Omicron variant.

“Even if (and it is still if) Omicron doesn’t cause more severe disease, the numbers of people who might be infected by its faster spread will create big challenges for NHS and economy – so we need to consider carefully (but quite quickly) what proportionate response needed.”

The SNP leader continued: “In meantime, all of us complying strictly with current protections will help. And even if you feel angry with a politician just now, please remember just how important compliance is for the health and safety of you, your loved ones and the country.”