Fury among Conservative MPs about Dominic Cummings’ trip to Durham during lockdown boiled over on Monday as a growing number joined calls for him to resign and expressed their frustration at having to deal with the political fallout. Influential backbenchers and former ministers, as well as those defending marginal former “red wall seats” were among those who spoke out about the damage they felt was being done to the party and the viability of future lockdown rules. Cummings responded to growing criticism in a press conference on Monday afternoon in which he gave further details on his movements during lockdown and said he did not regret his actions. None of the Conservative MPs who have been critical of him released a message of support or retracted their remarks after the press conference. The level of outrage and openness in speaking out against the prime minister’s most senior adviser is unprecedented, given the relative unity Johnson has enjoyed among his backbenchers by the virtue of his 80-strong majority. The Conservative MP for Carlisle, John Stevenson, tweeted: “People in positions of power have added responsibility. Mr Cummings holds such a position. Therefore in my view in the interests of the country Mr Cummings should resign.” On Monday morning the Tory MP David Warburton described how his father had died alone as a result of following the rules, and said Cummings’s actions gave the impression of “double standards”. He told BBC Breakfast: “People have made sacrifices, this is a difficult time, this is a time of national crisis. 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.” Damian Collins, the former chair of the digital, culture, media and sport select committee, who has previously clashed with Cummings over the latter being in contempt of parliament for not attending a committee hearing, tweeted: “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.” He said that having watched Cummings at his press conference, his response to the incident remained unchanged. Robert Largan, who took the former Labour seat of High Peak in 2019, said that if the reports were true that Cummings broke lockdown rules, he should resign. In a message to constituents on Facebook, he wrote: “We can’t have a position where it is one rule for the public and another for politicians.” The MP for the Colne Valley, Jason McCartney, told his constituents on Facebook that the “perceived hypocrisy of the rulemakers” potentially threatened the success of measures that might need to be introduced in the event of a second wave of coronavirus infections. He said on Sunday night that he believed Cummings’ position to be untenable. One senior MP with a northern seat said: “I think [Cummings] should go. It’s cut through. Massively. He’s a liability.” They said they had received more than 100 angry emails about Cummings in the past few days. The former sports minister Tracey Crouch did not call for Cummings to resign but did say the incident had left her “peed off” as she had been left dealing with constituents’ concerns. She wrote on Facebook: “I don’t really subscribe to the lynch mob, now or at any time … I am pretty peed off though. At a time when we should be still focusing on the remaining weeks of this pandemic, spending my days replying to understandably cross and angry constituents is not what I should be doing.” Other Conservative MPs to speak out included Martin Vickers, the MP for Cleethorpes, who told Sky News that Cummings should resign for having “undermined the government’s message”, and Tim Loughton, a former minister, who told the BBC: “Has the action of Dominic Cummings threatened to undermine the message of the government and its ability to carry on its work? I’m afraid regretfully it has and that’s got to be dealt with.” Other Tory MPs appeared to be engaging in an effort by the party’s whips to dampen down public anger by issuing nearly identical cut-and-paste messages asking constituents to “rest assured” they were passing on concerns about Cummings to the “relevant colleagues”. Cummings has maintained a defiant position throughout, telling reporters outside his home over the weekend: “Who cares about good looks? It’s a question of doing the right thing.” He added: “It’s not about what you guys think.” One Tory MP who has children and has isolated from other family members said there should be an immediate investigation into Cummings. Their inbox had also been swamped with emails, many from people who had never been in contact before. They said: “If he’s found to be in the wrong and he has broken lockdown, he should resign.” However, another Tory MP in a northern seat said: “A lot of people think this is just the remainiac establishment trying to get revenge.” In terms of long-term damage at the next election, they said: “Events will overtake this and four years is a long time.” The foreign secretary, Dominic Raab, tweeted in support of Cummings, saying he had given a detailed account of his actions and how he followed rules applicable to his family. The health secretary, Matt Hancock, said it was time to move on from the issue and get the country back on its feet. Tory MPs publicly criticising Dominic Cummings Steve Baker Simon Hoare Damian Collins Sir Roger Gale Peter Bone Caroline Nokes Craig Whittaker Julian Sturdy Robert Syms Paul Maynard James Gray Robert Goodwill Andrew Jones Tim Loughton David Warburton Robert Halfon Jason McCartney Martin Vickers Peter Aldous George Freeman John Stevenson Robert Largan