LONDON (AP) - Internal moves to topple British Prime Minister Keir Starmer erupted into public defiance on Thursday, as a key rival stepped down from the Cabinet and another paved the way for a possible leadership bid.

Health Secretary Wes Streeting emerged as the first high-ranking minister to exit Starmer's Cabinet on Thursday, a step viewed as groundwork for a leadership challenge.

Starmer confronts intensifying demands from his Labour Party to resign after the party's weak showing in last week's local and regional elections. The poor results have fueled widespread doubts among Labour MPs about his decision-making, strategy and command - a harsh setback for the leader who steered the party to victory in July 2024 following 14 years in opposition.

"You have shown courage and statesmanship on the world stage - not least in keeping Britain out of the war in Iran," Streeting stated in a sharp resignation letter. "But where we need vision, we have a vacuum. Where we need direction, we have drift."

"It is now clear that you will not lead the Labour Party into the next general election," he continued.

Known for his leadership aspirations, Streeting ranks among a select group positioned to contest Starmer. Such a move would not trigger a national vote, as Labour holds a five-year mandate and UK rules permit parties to swap leaders without an election.

Former Deputy Prime Minister Angela Rayner, another prospective contender, announced Thursday that she had settled tax issues with authorities, enabling her return after leaving the Cabinet last September. In comments to the Guardian, Rayner urged Starmer to "reflect on" his role and affirmed her readiness to "play my part" should Streeting launch a contest.

Contest to Replace Starmer Gains Momentum

Calls for Starmer to step down have surged since Labour's significant defeats in last week's local and regional polls, highlighting public discontent with a government struggling to fulfill commitments on economic expansion and better living standards.

A sluggish economy and persistent inflation have hindered Starmer's administration from meeting its goals despite a massive election win under two years ago.

British Prime Minister Keir Starmer engages with audience members after a speech at Horntye Park Sports Complex in St Leonards, Britain, in February. Photo by Peter Nicholls Pool via Reuters

Starmer has pledged to stay on, cautioning MPs that a leadership fight would create "chaos" when focus is needed on the cost-of-living squeeze and Middle East tensions.

His resistance received a lift Thursday from encouraging economic data.

Gross domestic product expanded by 0.6% in the first quarter, up from 0.2% previously, according to the Office for National Statistics.

Treasury head Rachel Reeves hailed the data as proof her approach is effective, promising more funds for public services and aid for those facing high living costs.

She warned against risking economic steadiness "by plunging the country in chaos at a time when there is conflict in the world."

The National Health Service also reported gains, with waiting times for appointments - a key focus for Streeting - dropping for the fifth consecutive month, a point he may leverage in a leadership run.

Streeting represents Labour's modernizing left faction, much like Starmer, while Rayner appeals to those feeling the party has drifted from its working-class base and advocating higher minimum wages and taxes on the wealthy.

Labour rules require a challenger to secure support from 81 of its 403 House of Commons members. More than that threshold have urged Starmer to go in recent days.

Additional contenders could join the fray.

Greater Manchester Mayor Andy Burnham is viewed as a strong possibility, though he would need a parliamentary seat, potentially via a by-election triggered by an ally's resignation.

Labour Rarely Ousts Its Leaders

Unlike the Conservatives, who frequently replace sitting prime ministers, Labour avoids such ruthlessness, noted Jonathan Tonge, politics professor at the University of Liverpool.

"They don't do ruthless on their leader," he said. "They don't tend to depose their leader. The Conservatives, they readily do ruthless."

Though the push against Starmer might fade, underlying divisions in UK politics suggest any lull would be temporary, Tonge observed.

"If a civil war opens up within a Labour Party that's supposed to be governing us at present, it's an extraordinary state of affairs given it's less than two years since Keir Starmer won one of Labour's greatest election victories ever," Tonge remarked.

"He's got a huge parliamentary majority, he's got more than 400 MPs, and yet his prime ministership may be on the brink of disintegration," he added.