British lawmakers looked likely Thursday to order an investigation into Prime Minister Boris Johnson for allegedly lying about whether he broke coronavirus restrictions by attending illegal gatherings during the pandemic.

The move would put more pressure on a prime minister whose grip on power has been shaken by claims he flouted the pandemic rules he imposed on his country and then repeatedly failed to own up to it.

The opposition Labour Party has called a House of Commons vote that, if passed, would trigger a watchdog committee probe of Johnson for allegedly misleading Parliament. Ministers found to have knowingly misled Parliament are generally expected to resign.

Labour leader Keir Starmer said his measure sought to uphold “the simple principle that honesty, integrity and telling the truth matter in our politics.”

“It is a British principle … guiding members from every political party in this House,” Starmer said. “But it is a principle under attack.”

Johnson’s Conservatives have a substantial majority in Parliament, but many lawmakers are uneasy with the prime minister’s behavior and could support the opposition move. The government initially said it would order Conservative lawmakers to oppose Labour’s motion, but later backtracked in the face of party disquiet and gave them a free vote — significantly raising the chances the measure will pass.

Johnson wasn’t attending the vote on a scandal that has rocked his leadership of the country and the Conservative Party. He was more than 4,000 miles (6,400 kilometers) away in India, insisting he wanted to “get on with the job” of leading the country.

Johnson was fined 50 pounds ($66) by police last week for attending his own birthday party in his office in June 2020, when people in Britain were barred from meeting up with friends and family, or even visiting dying relatives. Johnson is the first British prime minister ever found to have broken the law while in office.

He has apologized, but denied he knowingly broke the rules. Johnson’s shifting defense — initially saying there were no illegal gatherings, then claiming it “did not occur to me” that the birthday event was a party — has drawn derision and outrage from opponents, who have called for him to quit.

“The truth is simple and it’s this – he lied to avoid getting caught, and once he got caught, he lied again,” Scottish National Party lawmaker Ian Blackford said in the House of Commons.

Usually lawmakers are forbidden from accusing one another of lying, but Blackford was not reprimanded by the Speaker.

A growing number of Conservatives are uncomfortable about defending a leader who broke rules he imposed on the country. Until now many have indicated they will wait and see whether public anger translates into losses for the party at local elections across the country on May 5.

A few have called openly for Johnson to go.

“It is utterly depressing to be asked to defend the indefensible,” said Conservative legislator William Wragg. “Each time part of us withers.”

If lawmakers vote to send Johnson’s case to Parliament’s Committee of Privileges, the probe will not start until twin police and civil-service investigations into “partygate” have concluded.

Senior civil servant Sue Gray is investigating 16 events, including “bring your own booze” office parties and “wine time Fridays” in Johnson’s 10 Downing St. office and other government buildings. Police are probing a dozen of the events and so far have handed out at least 50 tickets, including those to Johnson, his wife Carrie and Treasury chief Rishi Sunak, and Johnson could still face more police fines.

Johnson and his allies argue that it would be reckless for the country to change leaders amid crisis including the war in Ukraine and a cost of living squeeze sparked by soaring prices for energy and food.

As he flew out to India for a two-day visit official focused on boosting economic ties, Johnson again denied knowingly misleading Parliament.

And he insisted he would lead the Conservatives into the next national election, due by 2024. He said aboard his plane to the western Indian state of Gujarat that there might be “some imaginary circumstances in which I might have to resign, but I don’t propose to go into them. I can’t think of them right now.”

(AP)