A Labour member of Parliament quit the UK opposition party’s government-in-waiting over leader Keir Starmer’s position on the Israeli-Hamas war, prompting questions about whether more resignations could follow.

Imran Hussain said on the social media platform X late Tuesday that he was stepping down as a shadow minister so that he could “strongly advocate for a cease-fire” in the conflict, a position Starmer has so far refused to adopt. He remains both an MP, representing the northern England city of Bradford, and a Labour Party member.

“It is clear that I cannot sufficiently, in all good conscience, do this from the front-bench given its current position,” Hussain wrote on the platform formerly known as Twitter. Although he “unequivocally condemned” Hamas’s Oct. 7 attack on Israel and said he believed that every country has the right to self-defense, he added that could never be “a right to deliberately violate international law on protecting civilians or to commit war crimes.”

The resignation is a moment of peril for Starmer, who is trying to hold his party together while backing Israel and distancing himself from the anti-Semitism accusations that dogged Labour under his predecessor, Jeremy Corbyn. Labour enjoys a healthy lead over the governing Conservatives in national polls ahead of a general election expected next year, but with more than a dozen members of his shadow ministerial team either demanding a cease-fire or endorsing the calls of others for one, the danger is Hussain’s departure prompts others to quit the front bench.

The discontent runs deeper: dozens of Labour MPs have backed a non-binding motion for a cease-fire, councilors have quit the party in Manchester, Oxford and Glasgow. Further complicating the picture for Starmer is the electoral math: there were 3.9 million Muslims in England and Wales at the last census, and past surveys have suggested they’re far more likely to vote Labour than back the Tories.

Starmer has called for “humanitarian pauses” in Gaza, tracking closely the position of both the UK and US governments, explaining in a speech last week that a cease-fire would allow Hamas, a designated terrorist organization, to attack again.

“Labour fully understands calls for a cease-fire,” the party said in a statement Wednesday. “Everybody wants to see an end to the shocking images we are seeing in Gaza. We need to see all hostages released and aid getting to those most in need. But a cease-fire now will only freeze this conflict and would leave hostages in Gaza, and Hamas with the infrastructure and capability to carry out the sort of attack we saw on October the 7th.”

UK Prime Minister Rishi Sunak has repeatedly defended Israel’s right to self-defense and criticized pro-Palestinian demonstrations such as a rally scheduled to coincide with Armistice Day commemorations this weekend. The government has put pressure on the Metropolitan Police to ban the event, setting up a potential showdown over the issue.

Met Commissioner Mark Rowley said in a statement Tuesday that their was no intelligence indicating a serious threat to public disorder, which would be required to ask the Home Secretary ban the protest. He didn’t rule out such action as a “last resort” if new details emerged.

Health Secretary Steve Barclay told Times Radio on Wednesday that the planned protest on a “sacred” day is “provocative,” and Sunak told broadcasters that Rowley will be held “accountable” for his decisions.

Rowley “has said that he can ensure that we safeguard remembrance for the country this weekend as well as keep the public safe,” said Sunak, who is due to meet the commissioner on Wednesday. “We’ve asked the police for information on how they will ensure that this happens.”

For Labour, Hussain’s resignation also underlined the ongoing fallout from an Oct. 11 interview Starmer gave to LBC radio, in which he appeared to back Israel’s “right” to cut off power and water from Gaza. Starmer later acknowledged the “distress” caused by his remarks and said he didn’t mean to back a siege on the territory.

Hussain said he was “deeply troubled” by the LBC interview and that, while he appreciated Starmer’s later clarification, he believed the party “needs to go further and call for a cease-fire.”

(Updates with Sunak remarks on protests in 10th, 11th paragraphs.)