Embattled British Prime Minister Keir Starmer yesterday vowed to prove his “doubters” wrong, as he sought to quell a growing threat to his leadership following disastrous local and regional polls.

Starmer pledged his ruling Labour party would do “better” as he tried to convince angry and restless lawmakers to back him in a crunch speech designed to reset his flagging premiership.

“I know that people are frustrated by the state of Britain, frustrated by politics, and some people frustrated with me,” he said during an address in central London.

“I know I have my doubters, and I know I need to prove them wrong, and I will,” added Starmer, who returned Labour to power after 14 years of Conservative rule in 2024.

Starmer has swerved from one policy misstep to another since then, and is engulfed in a scandal over the appointment -- and sacking -- of Peter Mandelson as UK ambassador to Washington, after revelations about the envoy’s ties to the sex offender Jeffrey Epstein.

The prime minister has failed to spur economic growth as British citizens continue to feel the effects of a years-long cost-of-living pinch, but has been praised for resisting US President Donald Trump over Iran.

Voters issued a damning indictment of Starmer’s 22 months in power in local elections Thursday, which saw huge gains for the hard-right Reform UK party and left-wing populists the Greens at Labour’s expense.

Starmer’s party also saw decades of dominance in Wales come to an end and failed to make up ground on the pro-independence Scottish National Party (SNP) in the devolved parliament in Edinburgh.

In his speech, Starmer acknowledged that “incremental change won’t cut it” with an increasingly disgruntled public, promising “a bigger response” in areas such as economic growth, closer European ties and energy.