Police have a photograph of Boris Johnson holding a can of beer at his lockdown birthday party in June 2020, according to reports.
It is understood to be among the 300 pictures submitted to the Metropolitan police by Sue Gray for their investigation into social gatherings which breached coronavirus regulations.
The prime minister is pictured with a can of Estrella beer standing next to the chancellor, Rishi Sunak, in No 10’s Cabinet Room, the Mirror has been told.
It was reported that the picture was taken by the prime minister’s official taxpayer-funded photographer, who was documenting the event in June 2020.
Labour’s deputy leader, Angela Rayner, told the newspaper: “The Downing Street photographer is funded by the taxpayer, and the public have every right to see the photos they pay to have taken, including any of the prime minister’s birthday party.
“Following the Met police investigation, the Sue Gray report must be published in its entirety with all accompanying evidence – photos, videos and testimony.”
Last month Downing Street acknowledged that staff “gathered briefly” at a surprise birthday celebration organised by Carrie Johnson but said that the prime minister only stayed for 10 minutes.
The chancellor is understood to have attended the event as he turned up for a Covid meeting, but had not been invited.
Sources told the Mirror that Johnson and Sunak were surrounded by No 10 aides in the Cabinet Room but there was no birthday cake.
Barrister Adam Wagner, an expert in Covid laws, said: “The legal question for the prime minister is whether he participated in the gathering. The fact that he was photographed holding a beer strongly suggests he did and therefore committed a criminal offence of the regulations.”
Downing Street said it could not comment due to the ongoing police investigation.
It comes after four of Johnson’s senior aides resigned in the space of 24 hours on Thursday.
His policy chief Munira Mirza, the director of communications Jack Doyle, the principal private secretary Martin Reynolds and the chief of staff Dan Rosenfield all quit.
There was pressure on Doyle and Reynolds to resign after their involvement in two Downing Street gatherings during lockdown emerged.