Cabinet ministers have pledged their support for Boris Johnson, as he faces calls to resign after admitting attending a drinks party in lockdown.

Meanwhile, the Prime Minister cancelled a visit to Lancashire after a family member tested positive for coronavirus.

Scottish Tory leader Douglas Ross and other senior backbenchers have urged him to stand down.

But cabinet ministers have urged MPs to wait for the outcome of an inquiry into alleged Covid-rule breaking at No 10.

And Commons leader Jacob Rees-Mogg dismissed Mr Ross as a "lightweight".

Mr Ross has written to the 1922 Committee, which oversees Tory leadership contests, to say he has no confidence in the prime minister.

If 54 or more of the party's MPs do so, a vote of confidence in Mr Johnson can go ahead - and if he loses, a leadership contest takes place. The chairman of the 1922 committee, Sir Graham Brady, does not reveal how many letters he has received until they have reached the threshold.

Northern Ireland Secretary Brandon Lewis told BBC Breakfast he "absolutely" backed Mr Johnson, adding: "You've got to let these investigations get to the full details and the full facts."

Foreign Secretary Liz Truss said she stood behind the prime minister "100%", while Chancellor Rishi Sunak said Mr Johnson had been "right to apologise", adding that he supported his call for "patience" while senior civil servant Sue Gray completes her investigation.

Deputy Prime Minister Dominic Raab said the PM had given a "very clear account" of what happened and Health Secretary Sajid Javid said "most people have accepted" the need to wait for Ms Gray's findings.

In the Commons, Mr Rees-Mogg said a future full inquiry into the pandemic would look at whether Covid-19 restrictions had been "proportionate" or "too hard on people".

"I think everybody understands, on all sides of the House, that people were obeying the rules, and these rules were very hard for people to obey," he added.

Mr Johnson's planned visit on Thursday to a vaccination clinic in Lancashire was cancelled and he will follow official guidance, including taking daily tests and limiting contact with other people, a Downing Street spokesperson said.

Mr Johnson admitted at Prime Minister's Questions on Wednesday that he had joined colleagues for drinks in the Downing Street garden on 20 May 2020 for around 25 minutes, to thank them for their hard work during the pandemic, but had "believed implicitly that this was a work event".

He apologised for his handling of the event, saying he understood people's "rage".

The gathering, described in the invitation as socially distanced, was attended by around 30 people, who were invited to bring their own alcohol. Food, including sausage rolls and crisps, was reportedly laid out on trestle tables.