The Metropolitan Police says it is not investigating allegations No 10 staff broke Covid rules in December of last year due to “an absence of evidence”.

A video obtained by ITV shows No 10 aides joking about holding a Christmas party amid lockdown restrictions, BBC reported.

Following an angry backlash, the PM’s former spokeswoman, who appears in the clip, stepped down from her role.

Labour has urged the police to pursue an investigation “without fear or favour”.

Shadow health secretary Wes Streeting said it was “simply implausible for the police to argue there is no evidence parties took place”, adding: “We have all seen the video involving No 10 staff referring to the party on 18 December.”

Boris Johnson has apologised for the clip of Downing Street staff and has asked senior civil servant Simon Case to carry out an inquiry into whether rules had been broken.

No 10 repeatedly insisted that there had not been a party and that all coronavirus guidance had been followed.