The UK main opposition Labour party leader, Keir Starmer, on Monday promised to step down if police fine him for breaching coronavirus laws by drinking beer and eating curry with activists.

"If the police decide to issue me with a fixed penalty notice, I would, of course, do the right thing and step down," he told a news conference but insisted: "I'm absolutely clear that no laws were broken."

The gathering took place in Durham, northeast England, in April last year, with a video later emerging of Starmer drinking beer and eating a takeaway meal inside a campaign office with party colleagues.

Starmer, a lawyer and former chief prosecutor for England and Wales, has repeatedly insisted it did not contravene rules against indoor gatherings since he was working.

'Mr Rules'

At the weekend, one of his top team described him as "Mr Rules" and on Monday he said he had self-isolated six times due to Covid.

"I did it because we followed the rules. The idea that I would then casually break those rules is wrong," he said, with his deputy, Angela Rayner, on Monday saying she too would resign if fined.

Police on Friday said they were reopening a probe into whether it breached lockdown rules, weeks after Prime Minister Boris Johnson was himself fined for breaking Covid restrictions.

Starmer said the difference between him and Johnson was that "he's been found to be in breach of the law.

"I think (there are) over 50 fines now in relation to Downing Street. And the prime minister has not stepped down," Starmer said.

"He and others in his party want the public to believe that we're all the same, that we will all act in that way. I'm here to make clear that is not the case."

Durham police looked into the event at the time and concluded that "no offence had been established", but reopened the investigation "following the receipt of significant new information over recent days".

That announcement came a day after local elections, in which Johnson's Conservative party was punished for his rule breaking.

The prime minister and his finance minister Rishi Sunak both received fines for attending a gathering in Johnson's office to celebrate his birthday in 2020.

London police are still investigating other potential breaches of the law by Johnson, who had previously denied breaking the rules he set.

When it emerged that Johnson was under police investigation, Starmer called it a "mark of shame" and demanded the prime minister resign.

"Even now he is hiding behind a police investigation into criminality in his home and his office," Starmer told MPs in January.

 'Decent thing'

Labour had to correct the parliamentary record last week after initially saying that deputy leader Rayner was not at the Durham gathering, and she on Monday also said that she would do the "decent thing" if fined.

"I've always been clear that I was at the event in Durham working in my capacity as deputy leader and that no rules were broken," Rayner said in a statement.

"Eating during a long day's work was not against the rules. We have a Prime Minister who has been found to have broken the rules, lied about it and then been fined.

"If I were issued with a fine, I would do the decent thing and step down."

Starmer says that he was recording Zoom videos and broke for food, adding that no restaurants or pubs were open at the time of the alleged offence, and that his hotel did not serve food.

"If you didn't get a takeaway then our team wasn't eating that evening," he said.

Johnson's wife Carrie was also among those fined for breaking Covid laws.