British Prime Minister Boris Johnson will face a vote of confidence on Monday, triggered by discontented lawmakers in his own party, according to the PA news agency.

Graham Brady, the chair of the 1922 Committee of Tory backbenchers, said he had received more than the required 54 letters of no confidence to spark a poll of the party’s MPs.

That vote will take place between 6 p.m. and 8 p.m. on Monday local time (1 p.m. to 3 p.m. ET).

If a simple majority vote against Johnson, he’ll be forced to step down as Conservative Party leader and his time as Prime Minister will end once a replacement is chosen.

A Downing Street spokesperson has said Boris Johnson “welcomes” Monday’s confidence vote in his leadership.

“Tonight is a chance to end months of speculation and allow the government to draw a line and move on, delivering on the people’s priorities,” the spokesperson said.

“The PM welcomes the opportunity to make his case to MPs and will remind them that when they’re united and focused on the issues that matter to voters there is no more formidable political force.”

Dozens of MPs have publicly expressed their dissatisfaction with Johnson’s recent performance. If Johnson fails in making his pitch on Monday, he’ll have to step down.