Boris Johnson is set to be grilled by Conservative and opposition MPs later on Wednesday over claims he attended a drinks event in the No 10 garden during lockdown.
He will be at the despatch box for Prime Minister’s Questions at noon, his first public appearance since details of the May 2020 event emerged.
Labour leader Sir Keir Starmer will be able to face Johnson after testing negative for coronavirus for a second day.
The Labour leader was forced to pull out of last week’s Prime Minister’s Questions session after testing positive for Covid-19 and has spent the time since in self-isolation.
But following negative tests on Tuesday and Wednesday he is clear to return to the Commons.
Johnson has faced intense pressure to resign over a lockdown-busting Downing Street drinks party that he allegedly attended along with his wife Carrie.
It comes after Martin Reynolds, the Prime Minister’s principal private secretary, sent an email to more than 100 Downing Street employees inviting them to “make the most of the lovely weather” in the garden during the first lockdown.
All four UK nations were under tough coronavirus restrictions banning groups from meeting socially outdoors when the message was sent on May 20, 2020.
Angela Rayner said she did not accept that Downing Street staff should have been able to meet up outside during the first Covid-19 lockdown because they were key workers or that the alleged gatherings could have been for work reasons.
The deputy Labour leader told BBC Radio 4’s Today programme on Wednesay: “I don’t accept that sending out invitations to ‘bring your own booze, the weather is lovely, come out into the garden’ to 100 staff as work, to be honest.
“I think it is very clear that that breaks the Covid rules. And what is astonishing is that the Prime Minister has had a couple of days now where he could have quite simply answered that question: ‘Yes or no – were you there at that party?’ And he has refused to do that.
“People have been reflecting about what was happening to them at the time in May and many people are still grieving their loved ones who they weren’t able to say goodbye to at the time, and to think the Prime Minister was laughing and partying is just unforgivable.”
An email exclusively shared with ITV News shows evidence of a party on May 20, 2020, when meeting more than one person outdoors was banned.
The email was sent to more than 100 employees in Number 10, including the prime minister’s advisors, speechwriters and door staff.
It said: “Hi all, after what has been an incredibly busy period we thought it would be nice to make the most of the lovely weather and have some socially distanced drinks in the No10 garden this evening. Please join us from 6pm and bring your own booze!”
ITV News understands around 40 staff gathered in the garden that evening, eating picnic food and drinking. Crucially, they included the PM and his wife.
The Metropolitan Police confirmed it is liaising with the Cabinet Office over the latest claims.
Douglas Ross, the leader of the Scottish Conservatives, said Johnson must resign as Prime Minister if he attended the party.
“You cannot be the head of the government that is asking people to follow these rules and then break those rules yourself,” Ross told STV News.
“If the Prime Minister or anyone misleads Parliament, you cannot come back from that. That is a resign matter.”