BORIS Johnson is facing a revolt from within his own party as MPs from across the political spectrum line up to condemn the prime minister and his chief adviser Dominic Cummings.

A storm of protest continues to rage not only over revelations the Prime Minister's most senior and most trusted aide broke the Government's own lockdown guidelines, but also due to Johnson's defence of Cummings.

Cummings travelled to County Durham in March to self-isolate with his family while official guidelines warned against long-distance journeys, apparently because he feared that he and his wife would be left unable to care for their son. Further reports also suggested he took a second trip to the North East in April.

Johnson fronted Downing Street's coronavirus briefing to back Cummings, saying he had "acted responsibly, legally and with integrity" and that "any parent would frankly understand what he did".

Dissent has come from inside Tory party ranks, with former minister Paul Maynard saying he shared people's "dismay" at the response, and was one of many MPs who insisted Cummings should quit or be sacked.

"It is a classic case of 'do as I say, not as I do' – and it is not as if he was unfamiliar with guidance he himself helped draw up," he said. "It seems to me to be utterly indefensible and his position wholly untenable."

READ MORE: PM faces public outrage after backing Dominic Cummings

Veteran Conservative Sir Roger Gale told the PA news agency: "I'm very disappointed, I think it was an opportunity to put this to bed and I fear that now the story is simply going to run and run."

Senior Tory MP Simon Hoare, who had already called for Cummings to go, later lamented Johnson's press conference, telling the Daily Mail: "The PM's performance posed more questions than it answered. Any residual hope that this might die away in the next 24 hours is lost."

Somerton and Frome MP David Warburton said Cummings was "damaging the Government and the country that he's supposed to be serving".

Speaking on BBC Breakfast on Monday morning, he said his own father had died alone as a result of the coronavirus lockdown.

"People have made sacrifices, this is a difficult time, this is a time of national crisis," he said. "In those sacrifices there really hasn't been the choice to use instinct. Instinct hasn't really been part of it.

"We've been tasked with following regulations laid down by the Government."

Tory grandee Lord Heseltine said it was "very difficult to believe there isn't a substance" in the allegations about Cumming's movements.

"I think these unanswered questions are now on the agenda," he told the BBC, "and I don't think that this anxiety about the Government's position will end until we know the whole story."

READ MORE: Ian Blackford slams Boris Johnson's ‘breathtaking arrogance’

Another Tory MP, Jason McCartney, said while it was important for people to show compassion during the crisis, Cummings had to go because the "perceived hypocrisy of the rule makers potentially threatens the success of any future measures" under a second wave of the coronavirus.

"We must have confidence that we are doing the right things for the right reasons and that we are all truly in it together. For that reason I believe Mr Cummings' position is now untenable," McCartney said in a Facebook post.

Drawing attention to "the moral hazard of Cummingsgate", Tory MP George Freeman retweeted an article from The Spectator which said Johnson's judgement was "now the issue".

In another tweet, Freeman appeared to bemoan what was missing from the responses of the PM and his main adviser, writing: "Today we needed: some humility; a clear acknowledgement that people would be rightly angry if they sensed double standards; a sincere thank you to the millions of people (including fathers) who have made sacrifices Dominic Cummings didn't; and a public apology from him".