LONDON (BLOOMBERG) - A Downing Street gathering took on the nature of a coronavirus lockdown-breaking party only after British Prime Minister Boris Johnson arrived and started pouring drinks, newspapers reported late Sunday (April 17), heaping more pressure before he meets lawmakers this week.

The Sunday Times reported that, at a gathering in November 2020 to note the departure of aide Lee Cain, Mr Johnson showed up, gathered people round a table and started drinking with them.

According to the Mirror, the premier urged those present to "let off steam".

The revelations threaten another difficult week for Mr Johnson, who was recently fined for breaking lockdown restrictions by attending his own birthday gathering in June 2020.

That's led to growing dissent within his Conservative party, including the resignation of a junior justice minister, and reinforced concern that next month's local elections in England and Wales will result in heavy losses for the Tories.

The latest allegation in the "partygate" saga sparked further criticism from the opposition Labour Party. Deputy leader Angela Rayner told the Guardian newspaper that it implied Mr Johnson had instigated the party.

"While the British public was making huge sacrifices, Boris Johnson was breaking the law," she said. "He has deliberately misled the British people at every turn.

"While Labour has a plan for tackling the cost of living crisis, Tory MPs are too busy defending the indefensible actions of Boris Johnson."

A Downing Street official declined to comment.

Mr Johnson is expected to make a statement to Parliament on Tuesday about the fine, where he will apologise for breaking the rules but insist he was not aware he had done so, the Telegraph reported.

Lawmakers will focus on whether the prime minister misled Parliament, a resigning matter, when he previously said parties did not take place at Downing Street and that Covid rules were followed at all times.

A YouGov poll found that almost two-thirds of Britons say Johnson should resign if he is handed further fines for breaking pandemic rules.

Separately, Scotland's First Minister Nicola Sturgeon was reported to Police Scotland after footage showed her apparently breaching the nation's face mask law on the council election campaign trail on Saturday, while the government was strongly advising that people continued to wear masks where appropriate.

Ms Sturgeon's office was contacted for comment but there was no immediate response.