Boris Johnson is under renewed calls to fire Dominic Cummings - from his own MPs. 

Reports surfaced last night that the 48-year-old made a second trip to County Durham from his London home despite social restrictions.

The claims were met with demands from opposition parties and members of the public for his resignation or sacking.

But now, Tory MPs appear to be breaking cover and joining the calls for Cummings to be removed from his post.

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Conservative MP Steve Baker, a prominent member of the 1922 Committee of backbench Tories, said the Prime Minister has no option but to dismiss his chief adviser.

He tweeted: "It is intolerable that Boris' government is losing so much political capital. Three changes are immediately required: 1 – Govt needs competitive expert advice 2 – Govt must insist on high software engineering standards 3 – Dominic Cummings must go."

He appeared to be the first Tory MP to contradict the government's stance.

Damian Collins, the Conservative MP for Folkestone and Hythe, said the government would be 'better off without' Cummings.

He said in a tweet: “Dominic Cummings has a track record of believing that the rules don’t apply to him and treating the scrutiny that should come to anyone in a position of authority with contempt.

“The government would be better without him.”

Simon Hoare said Cummins was 'wounding the Prime Minister and Government'.

Speaking on the Sophy Ridge On Sunday programme, Baker said it was time for Dominic Cummings to go.

"If he doesn't resign, we'll just keep burning through Boris's political capital at a rate we can ill afford in the midst of this crisis," he commented.

"It is very clear that Dominic travelled when everybody else understood Dominic's slogans to mean 'stay at home, protect the NHS and save lives'.

"And I think mums and dads who very much care about their children and who have been forgoing the childcare of their extended family will wonder why he has been allowed to do this.

READ MORE: Fresh calls for resignation as reports say Dominic Cummings made second Durham lockdown trip

"I really just don't see, as we approach the Prime Minister [appearing] at the liaison committee on Wednesday, how this is going to go away unless Dominic goes."

The SNP say the PM must answer the growing questions, and say the 'mounting rebellion' of Tory MPs shows they understand the 'lasting damage' this saga has caused.

Commenting, SNP Westminster Deputy Leader Kirsty Blackman MP said: "The Tory government now has serious and growing questions to answer about Dominic Cummings' rule-breaking and the Downing Street cover-up.

"Despite having eight weeks to get their story straight, the excuses are just not credible and do not stack up. This is now an issue of Boris Johnson's judgement and integrity.

"A mounting rebellion of Tory MPs have joined calls for Dominic Cummings to go. They understand the lasting damage this is doing to public confidence in the Tory government and its covid-19 response.

"The longer Mr Cummings stays in place - the more he will undermine the Tory government's credibility and the more people will question the Prime Minister's judgement.

"The SNP will continue to press for a Cabinet Office inquiry into the breaking of the rules and the Downing Street cover-up, which left the public in the dark for so long.

"As Scottish Tory leader Jackson Carlaw said: 'There cannot be one rule for bosses and another for everyone else'. Polling shows the majority of the public think Mr Cummings should go. Boris Johnson must come out of hiding and show Mr Cummings the door."

A YouGov poll now shows that 68 per cent of people think Cummings broke the rules, 52 per cent saying he should resign.

After the news of his first trip broke on Friday evening, Cummings talked to reporters outside his London home on Saturday afternoon, and said: "I behaved reasonably and legally."

And Downing Street responded to reports of his second trip, and said the claims were 'inaccurate'.