Andy Burnham could have free run at No10 as minister confirms he won't stand to replace Keir Starmer

Speaking to Sky News, Mr Jones, the MP for Bristol North West, went further than simply withdrawing, stating: "Andy Burnham is going to be the next Prime Minister."

When pressed on his decision, he responded: "I'm not," before adding: "Well, look, I was never planning or organising a leadership campaign like some of my colleagues."

Mr Jones questioned what purpose a contested race would serve, asking: "What would the benefit be to the country and to the party of a leadership contest?"

The senior minister explained that holding a leadership contest would leave insufficient time for the winner to prepare an autumn budget.

Mr Jones described his conversation with Mr Burnham about economic policy as "reassuring" before reaching his decision not to stand.

He revealed that more than 100 Labour MPs had voiced concerns, whether about the prospect of a contest, Mr Burnham's economic proposals, or simply feeling low following Sir Keir Starmer's departure.

Despite stepping aside, Mr Jones urged the frontrunner to provide greater detail on his economic plans for those worried colleagues.

When asked whether he could have mounted a credible challenge, Mr Jones indicated he believed sufficient parliamentary support existed, pointing to the significant number of MPs who had approached him with reservations.

On the question of who should become chancellor, Mr Jones appeared to caution against appointing Ed Miliband to the Treasury.

Setting out a series of criteria for whoever takes the Number 11 role, he said the next chancellor should not attempt to "control" the prime minister while also providing reassurance to markets, trade unions, Labour MPs and the public.

When asked directly whether Mr Miliband fell short of these standards, Mr Jones replied: "I will let you mark those tests, but those are the tests I think need to be met."

Regarding borrowing, Mr Jones acknowledged there was "room to borrow a little bit more" within current fiscal rules but emphasised alternative approaches existed to achieve Mr Burnham's goals "without broad brush borrowing and spending".

Former Armed Forces Minister Al Carns remains the only potential obstacle to Mr Burnham's coronation, having indicated he is seriously considering entering the race.

Mr Carns, who stepped down from his post earlier this month amid a dispute over defence spending, told the BBC on Tuesday that he was "pretty serious" about mounting a challenge but wanted to examine what policies Mr Burnham intended to champion first.

Should no rival candidate secure the 81 MP nominations required to appear on the ballot paper, Mr Burnham would be expected to take office by 18 July.

Such an outcome would make Britain's fifth prime minister in just four years.

The current Prime Minister has already permitted "access talks" between leadership hopefuls and civil servants, enabling Mr Burnham's team to receive government briefings once he demonstrates backing from 81 Labour parliamentarians.

Discussions continue over who might serve in a Burnham-led government, with several senior Labour figures being mentioned for prominent positions.

Former transport secretary Louise Haigh, Energy Secretary Ed Miliband, Home Secretary Shabana Mahmood and former health secretary Wes Streeting have all been linked with top cabinet roles.

According to the Times, James Purnell, who served alongside Mr Burnham in Tony Blair's Government, is being considered as a potential chief of staff.

Meanwhile, crossbench peer Jim O'Neill, who has been advising Mr Burnham, told the Guardian he favoured establishing a new independent body to enable additional infrastructure spending within fiscal rules, modelled on the Office for Budget Responsibility.

As for Sir Keir Starmer, Downing Street indicated on Wednesday that he plans to remain as a backbench MP for the remainder of this Parliament, dampening speculation about any future cabinet role.