A doctor is quitting the NHS in protest at Dominic Cummings’ refusal to resign despite allegedly flouting lockdown rules. Dr Dominic Pimenta has decided to resign because he fears that the behaviour of Boris Johnson’s chief adviser could help trigger a second wave of coronavirus and is angered by the government’s handling of the pandemic. Explaining his resignation in a statement shared exclusively with the Guardian, Pimenta said his decision was driven by the “laughable fairytale” explanation Cummings gave for his trip from London to Durham and nearby Barnard Castle, as well as by the adviser’s continued presence in Downing Street and cabinet ministers’ support of him. Pimenta, a cardiology registrar at a major London teaching hospital, has been a high-profile critic of ministers’ attempts to get to grips with the Covid-19 crisis. Two weekends ago, amid the gathering row over Cummings’ behaviour, he vowed on Twitter that he would resign if the No 10 adviser did not. The 32-year-old tweeted a photograph of himself wearing full personal protective equipment before returning to work in his hospital’s intensive care unit, where he has been working during the pandemic. In the tweet he said: “Haven’t seen my parents since January. Frankly, Cummings spits in the face of all our efforts, the whole #NHS. If he doesn’t resign, I will.” Doctors’ leaders said Pimenta’s decision was “very sad” and “a tragedy” and warned that other medics who have been battling the virus in recent months may follow. In his statement Pimenta cited the sacrifices made by the British public and NHS staff after the pandemic hit in March. “Cummings’ transgressions … and the subsequent doubling-down of ministers, including the prime minister, defending those actions, rewriting and threatening the rules of the lockdown to accommodate one man who simply won’t admit what he did was wrong, threaten to undo all that good, all that sacrifice,” he wrote. “It’s not just an affront to basic decency but a threat to our safety, to our collective ability to get through the next leg of this pandemic together and avoid that deadly second wave. A right and moral government would have asked for Cummings’ resignation.” Prof Andrew Goddard, the president of the Royal College of Physicians, said: “It is very sad that a colleague has felt the need to resign during this crisis. The NHS needs all the doctors it can get.” Dr Claudia Paoloni, the president of Hospital Consultants and Specialists Association, said: “It is regrettable that Dr Pimenta felt that he had no option but to resign his position. It is extremely concerning that he may not be the only doctor to take this step in the coming months.” Pimenta said he will use “a career break” to spend more time with his children and working with HEROES, a charity he set up in March to get PPE to the NHS frontline. “We have been privy to hundreds of requests for PPE. The risk to NHS staff throughout the pandemic highlights the importance of lockdown, and how awful it is to risk that again through this whole affair.” He had not planned to leave the NHS until Cummings’ alleged breaches of the lockdown were unearthed in a joint investigation by the Guardian and the Daily Mirror. “Prior to this I wasn’t thinking about leaving to be honest, we had spent weeks working with the government to augment their response during lockdown and everyone was pulling in the same direction. “It wasn’t so much as his behaviour as it was the consequences; the lack of an apology, the clear dismissal of the importance of the lockdown, the doubling down of ministers … After all that time and energy spent during the pandemic this feels like a total betrayal, especially if and when a second wave arrives.” Pimenta said he had this week submitted the paperwork needed to trigger his exit from the NHS medical training programme and would leave in October. However, if there is a second wave before then he will stay on until it has ended, he added. Dr Samantha Batt-Rawden, the president of the Doctors’ Association UK, said: “It is a tragedy to lose such a dedicated doctor from the NHS. Dr Pimenta’s reasons for quitting will no doubt resonate with the medical profession. Many doctors have been appalled at the government’s handling of the Covid-19 pandemic as the crisis has unfolded. “Despite the best efforts of those of us on the frontline, the UK has the highest excess deaths in Europe. Dominic Cummings’ actions were another blow to the morale of NHS staff who have been working so hard to keep patients safe. “No one would ever want to walk away from the frontlines during the peak of this crisis. However once the dust settles sadly I would not be surprised to see more resignations.”