LONDON: Embattled UK leader Rishi Sunak suffered a fresh blow Monday when a former ally defected to a right-wing populist party that is worrying the ruling Conservatives ahead of this year’s general election.

Lee Anderson announced that he was joining Reform UK, weeks after he was suspended from Sunak’s Conservative party over comments widely condemned as racist and Islamophobic.

The 57-year-old former deputy chair of the Tories became the first MP to represent Reform, whose honorary president is arch-Eurosceptic and Brexit figurehead Nigel Farage.

The fringe party is currently polling at around 10 percent in opinion surveys, which if replicated at the election could split the right-wing vote in key constituencies. That would make it even harder for the Tories, in power since 2010, to fend off a resurgent main opposition Labour party that is currently soaring ahead in national polls.

To blunt Reform’s impact, Sunak could take his party further rightward, continuing a trend in recent decades that has accelerated following the 2016 referendum on leaving the European Union.

Doing so risks alienating more socially liberal voters, however. Anderson is an MP in a so-called “Red Wall” seat of working-class voters in northern England that are crucial to both the Conservatives and Labour’s chances of winning the election.