Downing Street party: Tory MPs send angry message to Boris Johnson

It's a new year in Parliament. But things feel rather familiar.

The government had hoped the Christmas break would mean the anger over allegations of rule-breaking in Downing Street would fade into the background.

The events of the past 48 hours have made that impossible.

"We thought things would get better after Christmas" one grandee said. "Not yet".

The latest revelations - that dozens of Downing Street staff were invited to a BYOB (bring your own booze) event in the No 10 garden during the first lockdown - have left many Tory MPs furious.

One of those prepared to put that fury on the record was Nigel Mills, who told the BBC: "I think these revelations are much worse than the previous ones.

"The idea that during the worst lockdown - when you could only see one other person - that the people organising the rules were having a party is just unacceptable. It's indefensible.

"Anybody that organised that or who willingly attended it knowing it was a party, clearly can't be in charge of Covid policy."

That is clear message to Boris Johnson; if he was there, and knew that an event had be planned, he'd have to go.

"I think if he knowingly attended what he knew to be party, then he can't survive that," says Mr Mills.

There are other Conservative MPs who agree - but aren't prepared to say so on the record at the moment.

Some critics say they now think it's a matter of when - and not if - the prime minister will have to stand down.

One MP, from one of the 'Red Wall' seats traditionally held by Labour, told me they were "infuriated". Another MP spoke of waning authority in Downing Street.

Some used language we couldn't publish when venting their fury.

There is a feeling among some in the Conservative Party that the mood against the leader is hardening - and that is a very risky few weeks for Boris Johnson.

And some fear more revelations are coming.

But not everyone thinks things are terminal for the prime minister.

Others argue it's unlikely Mr Johnson will ultimately be held accountable for what went on in Downing Street in 2020 - instead, they predict senior staff may carry the can.

There is a familiar but growing school of thought that the PM needs to shake up his No 10 operation.

A minister said they expected Mr Johnson would survive - but would be weakened by the continuing question of whether his team were following the rules they were setting.

Tory MP Charles Walker has been a critic of many of the prime minister's lockdown decision.

He admits this week's events have been damaging.

"The prime minister and the No 10 team will know that there were significant errors of judgment made back in May 2020."

But he adds: "Not in mitigation but it was a fact they were all working extremely hard as many people were - they were working extremely hard in a sort of bunker environment - and I just think there was some poor decision making - I don't think it was malicious in intent."

At the moment, there aren't many Conservatives in Parliament who are offering a passionate defence of the prime minister. That's in part because Number 10 itself hasn't issued its own explanation.

But there are many Tory MPs who are demanding answers. They will be watching closely to see if they get any at Prime Minister's Questions today.