The Prime Minister, Boris Johnson and his wife Carrie have been accused of attending a drinks party in the garden of 10 Downing Street, on May 20, 2020, at the height of the pandemic when such gatherings were strictly banned by his own government.

His behaviour at this and other parties is now being examined by Sue Gray, a senior civil servant. Boris’s position will certainly become very uncomfortable if she finds that the Prime Minister violated lockdown rules.

What is damaging for Boris is that ITV News has published what appears to be the full email invitation sent by the Prime Minister’s principal private secretary, Martin Reynolds.

It has the subject line, “Socially Distanced Drinks! (OFFICIAL-SENSITIVE-No 10 ONLY)”

It then says: “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 No 10 garden this evening. Please join us from 6pm and bring your own booze!”

Strict Covid rules were in force at the time, which meant “you could only meet one other person from another household outdoors, with larger gatherings with people from other households banned”.

“Is this for real?” was the reaction of one of the staff who was “gobsmacked” to receive the email, in a message to another official shared at the time.

Another, shown to the BBC, said: “Um. Why is Martin encouraging a mass gathering in the garden?”

Those exchanges make it pretty clear that there were concerns at the time, the BBC reported.

Yet the event went ahead, with 30-40 people in attendance, a long table set out in the garden for drinks, crisps and sausage rolls with the Prime Minister and his wife in attendance, eye witnesses told the BBC.

Even some Tories have now turned against Boris.

Former Scottish Tory leader Ruth Davidson, who is now a Baroness, said: “Nobody needs an official to tell them if they were at a boozy shindig in their own garden. People are (rightly) furious. They sacrificed so much — visiting sick or grieving relatives, funerals. What tf were any of these people thinking?”

Former Prime Minister Theresa May wants to oust Boris as revenge for his role in toppling her.

Her former chief of staff, Gavin Barwell, now a peer, swiped: “Let me put this politely: it is not ‘entirely clear’ why the Prime Minister needs to wait for Sue Gray’s report to find out if he went to a party in his own garden.”

Boris is giving plenty of ammunition to the Opposition Labour Party, whose leader Keir Starmer said: “Boris Johnson, your deflections and distractions are absurd. Not only did you know about the parties in Downing Street, you attended them. Stop lying to the British public. It’s time to finally come clean.”

Shadow climate change secretary Ed Miliband, who is a former Labour leader, told Sky News: “How can he lead the country through these difficult times, get people to follow public health advice, if he has so flagrantly breached the rules?”

Scotland Yard is thought to be waiting to see if Gray’s inquiry identifies rule-breaking before considering whether further action is needed.

A spokesman for Scotland Yard said: “The Metropolitan Police Service is aware of widespread reporting relating to alleged breaches of the Health Protection Regulations at Downing Street on May 20 2020 and is in contact with the Cabinet Office.”

Queen protection

The airspace surrounding Queen Elizabeth II’s Windsor Castle residence in Berkshire, southeast England, will become a no-fly zone for security reasons from later this month, the British police said.