A Tory MP was “factually incorrect” to compare Boris Johnson’s attendance at a birthday bash in Downing Street to nurses having a drink at the end of their shift, the Royal College of Nursing (RCN) has said.

The Prime Minister has paid a fine in relation to the gathering in the Cabinet Room on June 19 2020 to mark his 56th birthday as it was a violation of coronavirus rules.

Lichfield MP Michael Fabricant had earlier told BBC News: “I don’t think at any time he thought he was breaking the law… he thought just like many teachers and nurses who after a very long shift would go back to the staff room and have a quiet drink.”

Writing to him, Pat Cullen, general secretary of the RCN, said: “We remain at the forefront of pandemic response. Despite political narrative, as health and care professionals we know the Covid-19 context is nowhere near over. While you position yourself with some authority as to the behaviour and actions of nurses during the pandemic, I’d like to inform you of the following facts.

“Throughout the pandemic – and still certainly, now – most days, nurses and nursing support workers, when finally finishing a number of unpaid hours well past shift end, will get home, clean their uniforms, shower and collapse into bed.

“Throughout the early pandemic, this was often alone, for the protection of others – kept away from family, friends and support networks. These shifts – in communities, in hospitals, anywhere people are – are long, unrelenting, understaffed and intense.

“At the end of one of the many hours, days and years we have worked, since recognition of the pandemic, I can assure you that none of us have sought to hang out and ‘have a quiet one in the staff room.’ There isn’t a site in England that would allow alcohol on the premises for any professional to consume during working hours.

“As frontline professionals, still dealing with the implications of the pandemic – understaffed, underpaid, overworked, exhausted, burnt out and still holding it together while doing the best we can for our patients. It is utterly demoralising – and factually incorrect – to hear you suggest that our diligent, safety critical profession can reasonably be compared to any elected official breaking the law, at any time.”

Mr Fabricant, who urged Mr Johnson to apologise, was talking about the incident in which the Prime Minister took part in a gathering of two or more people indoors, which was banned at the time.

Mr Johnson, speaking to broadcasters at Chequers, said he “fully respects” the outcome of the police investigation and that he accepted “in all sincerity that people had the right to expect better” from him.