THE Greens have called Boris Johnson a liar and insisted he must resign even if he is not fined for attending lockdown parties.

The party has said the Prime Minister must take more responsibility for fines handed out by the Metropolitan Police for celebrations held at Number 10.

Cops issued 20 fixed penalty notices to Downing Street staff for breaches of Covid-19 rules on Friday.

Since then, The Times has reported the scandal has reached the House of Commons, with at least two drinks parties being investigated by parliamentary authorities.

One of these was on the Commons terrace next to the Thames river which involved one minister and their special advisers.

It is believed some of the parties may have been at the same time as those held in Downing Street, such as the event on the eve of Prince Philip's funeral.

Scottish Greens health spokesperson Gillian Mackay said even if Johnson is not personally punished for breaching rules, he should still stand down.

READ MORE: Ex-ethics chief speaks out after lockdown fine

She said: “The question of whether the Prime Minister has himself received a fine yet or not is irrelevant.

"The fact is at least 12 parties took place in the Prime Minister’s residence when he was telling everyone else they were not allowed due to the public health crisis. We know the police are issuing fines for this rule-breaking, which Jacob Rees-Mogg may dismiss as ‘trivial’ but for the families of those who died and the millions who stayed away from loved ones during this difficult time, it is very serious indeed.

“Johnson told parliament no rules were broken at his house, but the actions of the Metropolitan Police have proved that was a lie.

"He must resign immediately.”

Cabinet minister Rees-Mogg dismissed concern over the parties as 'trivial fluff' at the Conservative spring conference last month. 

Johnson will reportedly not be interviewed by the Met as part of their investigation because the force is not speaking to those who have received questionnaires - and could potentially be fined - as part of the inquiries, according to ITV News.

The Met is investigating 12 events, including as many as six Johnson is said to have attended, and has sent out more than 100 questionnaires.