Andy Burnham could become prime minister within weeks after Wes Streeting announced he would not enter the race to succeed Sir Keir Starmer.
The former Greater Manchester mayor confirmed he would stand for the Labour leadership shortly after Sir Keir pledged an “orderly handover of power” in an emotional statement outside Number 10.
His chances of winning the premiership unopposed were boosted significantly minutes later when former health secretary Wes Streeting said he would back Mr Burnham in the upcoming contest.
Mr Streeting had been viewed as a potential leadership rival to Mr Burnham, but his decision not to enter the contest paves the way for a coronation as early as mid-July.
Announcing he would bid for the party leadership, Mr Burnham said Sir Keir’s resignation “marks the beginning of a transition”.
He said: “The Labour movement has always been at its strongest when it looks forward with confidence and purpose.
“This is what we will do from here and we will make sure this transition is a positive process of renewal for our party and our country.”
Giving his support to the new Makerfield MP, Mr Streeting said he had spoken with Mr Burnham “at length” and concluded he could “win the fight of our lives against the forces of nationalism”.
He added: “We could spend the summer exaggerating small differences, or we can roll up our sleeves and help him to deliver the change our party and our country needs.”
Sir Keir’s statement followed a weekend spent mulling his future with his family at Chequers, the Prime Minister’s country residence.
While his decision remained unclear early on Monday, ministerial allies and Number 10 staff gathered in Downing Street shortly before 9.30am in an indication Sir Keir was preparing to announce his resignation.
In a statement that competed with a protester playing the EU anthem Ode To Joy, Sir Keir said his party had asked “whether I am best placed to lead us into the next general election”.
He said: “I have heard the answer of my parliamentary party to that question, and I accept that answer with good grace.”
Defending his record, he pledged to give his successor “my full and unequivocal support, knowing that they will inherit a Britain that is far stronger and fairer than the one I inherited two years ago”.
With a wavering voice, he added: “When I leave the biggest job in the country, I shall spend more time on the most important job, being the best husband I can to my fantastic wife, Vic, who has been a rock by my side through good times and bad, and being the best dad I can to my beautiful children, who are my pride and joy.”
Sir Keir said he would ask Labour’s ruling National Executive Committee (NEC) to set out a timetable that would see a new leader in place by the time Parliament returns from its summer recess on September 1.
But the anointing of a new leader could come much sooner, with nominations closing on July 16.
Potential candidates have until then to amass the support of at least 81 Labour MPs.
But if Mr Burnham is the only candidate to have gained enough supporters by that point, he will become leader without a vote of the membership and is likely to become prime minister on either July 17 or 18.
Sir Keir’s decision to quit means the UK will now have its seventh prime minister in a decade.
Reform UK leader Nigel Farage called for a general election in the wake of Sir Keir’s resignation, tweeting: “If Labour thinks it can shove another professional politician into No 10, it has another thing coming.”
Other opposition figures stopped short of demanding an election, but urged Sir Keir’s successor to be bold.
Liberal Democrat leader Sir Ed Davey said: “Whoever becomes prime minister needs to drop the caution and complacency and show the ambition our country deserves.”
Green leader Zack Polanski said the country needed “a bold change of direction”, adding: “The time for half measures and sticking plasters is long gone – if he becomes the next PM, Burnham must be bold or he will be bust.”
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