U.K. Prime Minister Rishi Sunak is facing calls from Conservative lawmakers to adopt an immigration cap, as he comes under pressure to move his party further to the right after it was routed in last week’s local elections.

While internal critics of Sunak decided against trying to replace him, prominent party members renewed their attacks on the leader after the Conservatives lost almost half the local council seats they were defending. Keir Starmer’s resurgent Labour Party also won 10 out of 11 mayoralties up for grabs, increasing its vote share in London and toppling the popular Tory mayor Andy Street in the West Midlands by just 1,500 votes.

Now, Sunak is facing calls to consider policies including an immigration cap and a withdrawal from the European Court of Human Rights, even though the prime minister has urged the party to "stick to the plan” ahead of a general election expected in the second half of the year. Although many of its seats were captured by Labour and other left-leaning parties such as the Liberal Democrats and the Greens, some Conservatives worry the populist Reform U.K. founded by Brexit-campaigner Nigel Farage poses a bigger threat.