LONDON (AP) — Andy Burnham, Britain's newest lawmaker and likely its next prime minister, was meeting Labour Party colleagues on Tuesday, in preparation for a leadership contest in which he may be the only contender.

Burnham is the strong front-runner to replace Prime Minister Keir Starmer, who announced Monday that he would step down within weeks after two years in office marred by missteps and judgment errors that eroded his standing with his party and the public.

READ MORE: How UK's Keir Starmer went from election landslide to downfall

Burnham, a former Cabinet minister who served since 2017 as mayor of Greater Manchester, won a special election last week for a seat in Parliament with the express aim of challenging Starmer for the leadership.

Burnham's chances got a big boost on Monday when former Health Secretary Wes Streeting, who was considered his main rival, announced his support.

The U.K. parliamentary system allows governing parties to change leaders — and thus prime ministers — without the need for a national election. The next general election doesn't have to be held until 2029.

Nominations for the Labour leadership will open on July 9 and close a week later. If Burnham is the only contender, he could be prime minister by July 17. If there is a contest, the winner should be in place by the time Parliament returns from its summer break on Sept. 1.

Burnham's economic plans aren't yet known

Burnham was a popular mayor of Greater Manchester, overseeing a period of rapid regeneration for the city in northern England where the Industrial Revolution was forged. He has pledged to repeat his signature brand of "Manchesterism" on a national scale.

Many Labour members hope Burnham's people skills and charisma can connect with the public more than the stolid, managerial Starmer could ever do.

But Burnham's policies in many areas are unknown and untested. Some Labour lawmakers want to see a party election contest where he would face public debate and scrutiny.

Burnham is expected to make a speech next week outlining some of his economic plans.

Former Armed Forces Minister Al Carns, who quit this month to protest what he saw as inadequate defense spending, said that "we need to have a clear and concise discussion about what this country wants to be."

He has suggested that he might run for the leadership, but told broadcaster ITV that "I'm not ready to make a decision on this in any way, shape or form."

Others have suggested Darren Jones, a senior Cabinet minister and Starmer ally, should run, though he has yet to comment.

Potential candidates need the support of at least 81 Labour lawmakers, a fifth of the parliamentary party, to run.

Many argue that a leadership contest will only focus attention on the party's internal divisions and extend a period of political uncertainty.

Starmer told the weekly meeting of his Cabinet on Tuesday that he will try to make the transition to his successor as easy as possible. He told ministers that he wants an "orderly transition" and for whoever replaces him to succeed, his office said.

While Starmer wants to carry on with business as usual, he's not allowed to make new major policy announcements or spending commitments during what remains of his time in office.

Starmer won a landslide but stumbled in office

Starmer resigned on Monday after a weekend considering his future, acknowledging that the Labour Party no longer thinks "I am best placed to lead us into the next general election."

He was the sixth prime minister in a decade to stand outside No. 10 Downing St. and announce a departure. It comes as Britain marks the 10th anniversary of its vote to leave the European Union, a decision that still roils the country's economy and politics.

READ MORE: 6 leaders in 10 years. A look at the quick succession of British prime ministers

After weeks of insisting that he would fight to keep his job, Starmer conceded to growing pressure to hand over to a new leader who can try and revive the government's flagging fortunes. He led Labour to a landslide election victory in July 2024, but his popularity and that of the party have plummeted since then.

Starmer has struggled to deliver promised economic growth, repair tattered public services and ease the cost of living. He has been hamstrung by repeated missteps, including his decision to appoint Peter Mandelson, a scandal-tarnished friend of Jeffrey Epstein, as U.K. ambassador to the United States.

Labour is losing liberal voters to the growing Green Party and facing a rising Reform UK, the Nigel Farage -led anti-immigration party that consistently leads in nationwide opinion polls.