Image source, PA Media

Andy Burnham has made no secret of his ambition for the top job.

The Manchester Mayor has strong support from Labour MPs and polls suggest he is the most popular Labour politician with voters.

He can point to a long track record of governing, having served as Greater Manchester mayor for almost a decade, earning him the nickname "the King of the North". He also served as a minister in Tony Blair's government and a cabinet minister under Gordon Brown.

And with Josh Simons' resignation, Burnham now has an opening to return to Parliament.

But there are a number of hurdles between then and now.

Firstly, he will need to approval from the NEC, Labour's governing body, to stand. He would then need to win the subsequent contest - all of which could take several weeks.

The upcoming Makerfield by-election would stand as a "good test" of whether Andy Burnham can "turn the country" by beating Reform, says a serving member of Labour's National Executive Committee.

The committee will consider Burnham's application to run as the party's candidate in the by-election, with Gemma Bolton telling BBC Radio 4's The World Tonight programme that it's right he should be a choice for the members.

She says: "He's a strong candidate, he's popular in Manchester, and he should be given the chance to stand."

Earlier this evening, John Simons announced he will resign as the Labour MP for Makerfield to allow Andy Burnham to try to run for a seat in the Commons.

Simons won the Greater Manchester seat in the 2024 election. It was his first time standing for Parliament.

The constituency boundaries were changed slightly in that election, but the seat has been Labour for decades.

In the 2024 election, Simons won with 18,202 votes - 45.2% - with Reform UK coming second with 12,803 votes, 31.8% of the vote.

You can see the full 2024 general election results for Makerfield on the BBC here.

Joe Pike
Political correspondent

Reform UK has already opened applications to be its candidate for the Makerfield by-election.

Party members were emailed about the selection process this evening, and the deadline for applications is Sunday.

“We’re determined”, said one senior party figure. “It’s going to be a tight fight.”

The constituency on the western fringes of Greater Manchester has a Labour majority of 5,399 and has been a party stronghold for decades.

Yet at last week's local elections, across the eight Makerfield wards that voted, about 50 per cent of people backed Reform UK.

Image source, PA

As we've been reporting, Labour MP for Makerfield Josh Simons has said he will resign his seat so Andy Burnham can try and run for Parliament. If elected, Burnham would have to resign as Mayor of Manchester to take his seat.

Here's how some of the other parties have reacted:

Lib Dem Cabinet Office spokesperson Lisa Smart says: "The arrogance of these men is staggering. To believe that representing a community is a gift to be handed to your mate shows utterly, out-of-touch contempt."

She says Labour should pay the cost of running the Greater Manchester mayoral election - the last one cost the taxpayer around £4.7m - saying it would result from Labour's "internal psychodrama".

Leader of Reform UK Nigel Farage says his party "will throw absolutely everything" at the Makerfield by-election - his party came second there in the 2024 general election, and hammered Labour there in last week's local elections.

Green Party leader Zack Polanski says Burnham "will need to make clear which version of him is going to show up", asking if it will be "the politician who has been part and parcel of the Labour establishment for decades", or the "popular mayor" who has "expressed support to make changes to the failed economic model".

The Conservatives have not commented directly since Burnham's announcement, but in a post on social media leader Kemi Badenoch said the Tories would offer "an alternative to this Labour chaos".

Image source, EPA/Shutterstock

Wes Streeting has congratulated James Murray on his appointment as health secretary.

He says in a post on X that the Ealing North MP "inherits a wonderful team and an important mission", adding that he has his "full support".

Streeting said in his resignation letter earlier today that he had "lost confidence" in Keir Starmer's leadership, so it would be "dishonourable and unprincipled" to remain in post.

The deputy council chair of the British Medical Association said Streeting's resignation comes at a "critical time", while a think tank chief executive said the next health secretary will face "immediate choices" that will shape the health and care system for years to come.

Image source, EPA/Shutterstock

James Murray has replaced Wes Streeting as health secretary following his resignation earlier today.

Murray, who represents Ealing North, previously served as chief secretary to the Treasury from September last year.

He was first elected as an MP in 2019, with his previous roles also including exchequer secretary to the Treasury and shadow financial secretary.

Murray served as the executive member for housing and development at Islington Council from 2010 until 2016, after being elected as a councillor for the authority in 2006.

He was London's deputy mayor for housing from 2016 to 2019 before he became an MP.

Image source, Getty Images

Northampton North MP Lucy Rigby will take James Murray's role as chief secretary to the Treasury, Downing Street confirms.

Rachel Blake, MP for Cities of London and Westminster, will replace Rigby's old role, becoming economic secretary to the Treasury.

Former Chief Secretary to the Treasury James Murray has been appointed as the new health secretary, Downing Street says.

The news of the Ealing North MP's appointment comes after Wes Streeting's resignation from the position earlier today.

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While Andy Burnham's chances of returning to Parliament appear to have improved thanks to Josh Simons's resignation, the Greater Manchester mayor still has a ways to go before challenging the prime minister.

Following the Labour MP's decision to step aside, Burnham needs to be chosen as Labour's candidate for any upcoming by-election.

This decision is made by the party's National Executive Committee, which back in February chose to block Burnham from running in the Gorton and Denton by-election.

He then needs to win the seat after being permitted to run. All the while Labour faces increasing pressure from Reform and the Greens.

Once back in Parliament, he would need to persuade 81 Labour MPs that he is the right choice to replace Keir Starmer to run in any leadership contest.

Our political reporter Kevin Fitzpatrick speaks more on the topic in the clip below:

Makerfield by-election campaign bound to be unconventionalpublished at 20:02 BST

20:02 BST

Iain Watson
Political correspondent

The campaign will be unconventional to say the least.

A former party strategist tells me the only viable campaign strategy is to stand as the vehicle to remove Keir Starmer from Downing Street.

Or if Starmer has already announced a date for his departure, then Burnham will have to run against the record of that government – of the mistakes and U-turns, and put forward a bolder and more imaginative offer.

Iain Watson
Political correspondent

The offer from Josh Simons to stand aside for Andy Burnham brings several issues in to sharp relief.

First, he is from a different wing of the party to Andy Burnham.

The Greater Manchester mayor’s supporters have been quick to badge him as the "unity" candidate and the hope is that this will put further pressure on Keir Starmer to set a timetable for his departure from Downing Street.

One of them said to me: "This proves that Andy Burnham is the only person who can unite the coalition the Labour Party needs to change the country. This is the way forward that the party can unite around and the PM should set out an orderly process to deliver it."

Second, it has dealt Starmer’s authority a blow. The BBC has been told that No 10 won’t ask Labour’s ruling national executive to block Burnham’s candidacy in Makerfield, as it did in Gorton and Denton.

This suggests the herd has moved and can’t be shepherded back by Starmer’s allies.

Third, it’s a test of Andy Burnham’s popularity.

The seat was once safe Labour territory but no longer. It has a majority of less than 6,000.

Reform is in second place. At the recent council elections in the area, Nigel Farage’s party gave Labour a drubbing. If Burnham fails to win, his long-held leadership ambitions are over.

Win, and the prize is almost certainly the Labour leadership, and No 10, as he will have demonstrated that he has turned the electoral tide with at least some voters who have drifted to Reform coming back - in contrast to Starmer, who has presided over tumbling poll ratings.

Becky Morton
Political reporter

Image source, PA Media

Andy Burnham is no stranger to Labour leadership contests.

More than 10 years ago he ran twice, unsuccessfully, for the top job. Now he's backed by many Labour MPs as the party's best chance of recovery, after months of languishing in the polls and a devastating set of election results.

The only problem? He's not an MP - a requirement to stand as Labour leader.

In January, he was knocked back by Labour's ruling National Executive Committee (NEC) when he sought to stand in a by-election.

But he has now managed to find a Labour MP willing to stand down to give him a chance to get back to Westminster to challenge Sir Keir Starmer.

It is not a done deal - you can read more in our news story.

Jack Grey
Live reporter

Image source, Getty Images

Shortly after 17:00 BST, Labour's Makerfield MP Josh Simons announced that he was resigning to make way for Greater Manchester Mayor Andy Burnham to seek a return to Parliament.

Here's what followed:

• In his statement, Simons said his decision had "not been easy" but that Burnham could "drive the change" he says the UK needs
• A few minutes later, Burnham confirmed that he would be seeking permission from Labour's National Executive Committee (NEC) to stand in the seat
• Burnham said he was looking to "bring the change we have brought to Greater Manchester to the whole of the UK"
• The NEC previously blocked Burnham standing as Labour's candidate in the Gorton and Denton by-election in February, which was won by the Greens
• The BBC understands that the prime minister will not seek to block Burnham standing as Labour's candidate in Makerfield

All of this follows the resignation of Health Secretary Wes Streeting earlier this afternoon, who said he had "lost confidence" in the prime minister. However, no leadership contest has yet been triggered.

A Streeting supporter told the BBC that the former health secretary "wants Andy to have a chance to declare his intentions" before going ahead with a leadership challenge.

To trigger a contest, any prospective challenger would need the backing of 20% of the party's MPs - or 81 out of 403.

Image source, Reuters

We continue to catch you up with the latest developments in British politics. Streeting's resignation was not the only breaking news we reported on in this action-packed day:

Plot twist - Rayner 'cleared' over tax row: At 07:00, an unexpected announcement came from another potential leadership contender. Angela Rayner says HMRC cleared her of wrongdoing over her tax affairs - the message she seems to want to get across is she’s back in the fray, our political correspondent writes.

Case closed: Hours after Rayner's announcement, the BBC's political editor is shown an HMRC letter to her lawyers verifying that the tax authority now considers the row over her stamp duty as closed.

Rayner calls for reflection from Starmer: The former deputy prime minister tells The Guardian that the PM will "have to reflect" on whether he's still the right man for the job. She adds that she is ready to "play my part" to deliver on the change Labour promised to voters.

Don't plunge country into chaos - chancellor: Chancellor Rachel Reeves warns MPs not to put "economic stability" at risk by "plunging the country into chaos".

Ben Hatton
Live reporter

Image source, PA Media

Today has been the kind of day in Westminster where recaps like this have had to be hastily rewritten, and then rewritten again as events twisted and turned.

Health Secretary Wes Streeting resigned, the latest in a series of departures from the government following last week's elections - and the first of a member of cabinet. Below is a quick recap of how the latest resignation unfolded.

All eyes on Streeting: We went into the day with Wes Streeting's allies having said on Wednesday they expected to him to challenge Starmer as soon as today.

Jostling for position: That's how our political editor Chris Mason describes the scene later in the morning. With nearly 90 Labour MPs calling for Starmer to go, and more than 150 giving him his backing, MPs are reportedly receiving calls from both those supportive of Starmer and supportive of Streeting.

Starmer retains confidence in Streeting: That's the word from Downing Street around lunchtime, with Starmer's spokesperson saying he would fight any challenge.

Streeting resigns: Around an hour later - amid growing speculation over whether Streeting would actually make a move - he resigns as health secretary but stops short of triggering a challenge. He calls for a "broad" contest with the "best possible field of candidates". That's widely interpreted as meaning a longer timeframe that would allow Andy Burnham - who would need to be elected an MP first - to stand.

Starmer responds: In a letter to Streeting released around 5pm, the PM says Labour is in "a battle for the soul of our nation" and part of that is delivering on "our promise to turn the page on the chaos". That followed some toing and froing over whether Streeting has the numbers.

Joe Pike
Political correspondent

Today is the day a Labour leadership contest effectively started - even without either a vacancy or any declared contenders.

We’ve had Angela Rayner’s 06:00 announcement about settling her tax affairs, Wes Streeting’s 13:00 resignation as health secretary, and shortly before 18:00 Andy Burnham's statement that he wants to stand in the Makerfield by-election.

None of them have explicitly said they want to succeed Keir Starmer, but behind the scenes campaign teams are forming and Labour MPs are starting to decide who they fancy.

It leaves the prime minister in an awkward position. It’s not clear any of his rivals have the 81 MPs needed to actually challenge him, yet many in Labour now seem firmly focused on who’s next.

Henry Zeffman
Chief political correspondent

Keir Starmer will not seek to block Andy Burnham from becoming the Labour candidate in Makerfield, the BBC understands.

No 10 has indicated to Labour MPs that it will not seek to block Burnham.

An ally of Starmer says: "Keir is focused on bringing the party together so it can tackle the issues facing working families.”

Chris Mason
Political editor

In the four years I’ve done this job, there have been four prime ministers. So when it comes to governments facing implosion, either at the hands of their own MPs or the electorate, this isn’t my first recent rodeo.

The stimulus for messes like this, ultimately, is public sentiment - Labour’s pummelling in those elections last week and the slow burn of frustration in Keir Starmer from lots of Labour MPs.

But the short term consequence is paralysing for any government. And that paralysis looks likely to last for a bit.

Tonight, after a day of frenzied noise, briefings and no shortage of wild conjecture - the cabinet has lost a health secretary, the mayor of Manchester has found a parliamentary seat to fight, but there is still no formal leadership contest.

Allies of the prime minister claim to me privately Wes Streeting’s nowhere near the magic number of 81 MPs to trigger one.

His team insist he is and they wanted to leave space for Andy Burnham to intervene. Team Burnham insist there’s been no coordination with the Streeting camp.

Meanwhile, for now at least, Starmer remains defiant, bullish, if - in all likelihood - fatally undermined. And this whole saga is only just getting going.

Joe Pike
Political correspondent

Winning the Makerfield by-election could be a major challenge for Andy Burnham, if indeed he becomes his party’s candidate.

For decades the constituency on the edge of Greater Manchester was considered one of Labour’s safest. The party’s majority from the 2024 general election stands at 5,399.

But Reform UK hammered Labour there at the local elections last week, and Nigel Farage has already committed to “throwing absolutely everything” at the by-election.

Before that campaign begins, a subcommittee of Labour’s ruling National Executive will decide whether Burnham can put himself forward to be the party's candidate.

In January, Keir Starmer helped block Andy Burnham for standing in a different by-election in the north-west of England.

This time round the prime minister is in a far weaker position, and many of his allies believe Starmer can no longer block the ambitions of the Greater Manchester mayor.