LONDON: British Prime Minister Boris Johnson faced three new calls to resign from within his own Conservative Party on Wednesday, adding to the steadily growing number demanding he quit over a series of parties at Downing Street during lockdown.

Police are investigating 12 different gatherings at the heart of the British state for breaches of the government's own COVID-19 public health laws following an internal inquiry that criticised a "serious failures of leadership".

Weeks of media revelations about the parties - including a bring your own booze event attended by Johnson - have seen Conservative opinion poll ratings slump and shaken many of his lawmakers' faith in the leader who won them the 2019 election.

"I cannot reconcile the pain and sacrifice of the vast majority of the British public during lockdown with the attitude and activities of those working in Downing Street," said Gary Streeter, member of parliament for a region in southwest England.

"I have now submitted a letter seeking a motion of no confidence in the Prime Minister," he wrote on Facebook. Streeter's statement took the number of those publicly declaring they have asked for a confidence vote to seven, though several more have either called for Johnson to resign or openly criticised him.

A confidence vote can be triggered if 15% of the 359 Conservative members of parliament write letters demanding one to the chairman of the 1922 Committee. The number of letters currently submitted is not made public.

Johnson has so far weathered the pressure by announcing a series of policies popular with his right-leaning party and promising to reform his top team and get on with rebuilding from the pandemic.

Earlier on Wednesday he launched his plan to address regional inequality - one of the key promises that helped him persuade million of voters to switch their political allegiance and back his party in 2019.

Conservative lawmakers Anthony Mangnall and Tobias Ellwood earlier said separately they had submitted their letters.

"It's time to resolve this so the party can get back to governing," Ellwood, chair of parliament's defence select committee and a former junior minister, told Sky News.