A senior Tory compared Boris Johnson's Partygate fine to getting a speeding ticket then tried to U-turn in an excruciating radio interview.
Northern Ireland Secretary Brandon Lewis was sent out to defend the Prime Minister ahead of a crunch Commons statement later, where Mr Johnson is expected to apologise to MPs for breaching his own Covid laws.
Mr Lewis said the Prime Minister had accepted and paid the fine issued by the Metropolitan Police last week over his surprise birthday gathering in Downing Street on 19 June 2020.
But he tried to minimise the severity of the PM's rule-breaking by claiming the Partygate penalty was similar to receiving a speeding fine, as both offences result in fixed penalty notices.
In an awkward clash, Mr Lewis then tried to wriggle out of his own comments when challenged by Radio 4 Today programme presenter Mishal Husain.
Asked if the PM accepted the rules were broken, Mr Lewis said: "He accepts the fine, he accepts the police decision which is that a rule was broken. That's why he's paid the fine and apologised."
But he tried to claim Mr Johnson had not misled Parliament with his repeated claims that no rules were broken in Downing Street during the pandemic.
Ministers who mislead Parliament are expected to resign but Mr Lewis offered a flavour of the PM's defence, saying he made the comments "in the full belief they were correct".
"He also accepts the police have come to a different view over the last week or so," he added.
Asked if "lawmakers can be lawbreakers", Mr Lewis said: "Well look sadly we have seen over the years, whether it's been Labour ministers or Conservative ministers having fines for different things."
Asked who he was referring to, Mr Lewis said: "We've seen reports of ministers who have had - both the Labour party and the Conservative party over the years - whether it's been speeding fines and things like that, if you accept that decision..."
Pressed on whether this had happened while in office, he said: "I believe so, I'm just going on reports I've seen over the weekend."
When he was challenged to back up his comments, he then pivoted: "If somebody gets a speeding ticket, I'm not in any way trying to equate a speeding ticket somebody has had with the situation, the sacrifices people have made through Covid.
"I want to be really clear about that."
But the presenter retorted: "You've actually literally just done that."
Mr Lewis then said he was only asserting that accepting a fixed penalty notice and paying the fine was the right way to handle it.
Earlier in his broadcast round, Mr Lewis explicitly told Sky News that the PM's penalty was akin to ministers who have previously received parking fines.
He said: "I think we do see consistently, whether it is through parking fines or speeding fines, ministers of both parties over the years have been in that position.
"We've had prime ministers in the past who have received penalty notices, from what I can see, and also front bench ministers.
"I saw there was a parking notice that Tony Blair had once. We've seen front bench Labour ministers and, let's be frank, government ministers as well."
He added: "You've asked me, can someone who sets the laws and the rules, can they also be someone who breaks the rules.
"That clearly has happened with a number of ministers over the years."
No10 aides said Mr Johnson is expected to “wholeheartedly apologise” to MPs at today’s showdown.
But the PM is expected to insist he did not break Covid laws, despite paying the fine and having said sorry for his breach.
He also faces a vote as early as tomorrow on whether he will be referred to the Commons privileges committee to investigate if he had misled MPs over Partygate.
If guilty, he could be suspended from Parliament.
Labour leader Keir Starmer, a former director of public prosecutions, told ITV's Lorraine: "I have never had anybody break down in front of me because they couldn't drive at 35mph in a 30mph zone.
"I have had no end of people in tears - in real bits - about complying with rules that really, really hurt them."
Liberal Democrat Leader Ed Davey said: "The excuses of Conservative ministers are getting more pathetic by the day.
"There is a massive difference between getting a parking fine and Boris Johnson breaking his own lockdown rules.
"It is an insult to bereaved families and all those who made huge sacrifices while Johnson partied in No 10.
"Conservative MPs need to discover their moral backbone and sack Johnson instead of defending the indefensible."
Mr Johnson's future is in the hands of Tory MPs, who will decide whether to trigger a no-confidence vote in their leader.
Former defence minister Tobias Ellwood said there were "many MPs" who were "very concerned by where we're going" and argued that Mr Johnson should call a confidence vote.
"We have to defend this at the next general election," he told BBC Breakfast.
"We've got some more fixed penalty notices likely to come forward, Sue Gray's report to conclude, and, of course, those important local elections on May 5.
"If I was the Prime Minister, I would show leadership here... and say that 'these are difficult times, I will give you the opportunity to support me through an actual vote of confidence'."
But Sir Geoffrey Clifton-Brown, treasurer of the 1922 Committee of Tory backbench MPs, said it was "certainly not in the country's interests to think about replacing the Prime Minister", given the war in Ukraine and the cost-of-living crisis.
Sir Geoffrey said he wanted to see "all the evidence", which would include whether more fines are issued, the full publication of senior civil servant Sue Gray's report into the party claims and what verdict the British people give in the local government elections.
