Exact date Andy Burnham looks set to become UK prime minister

Andy Burnham looks set to become UK prime minister on July 20 following overwhelming support from Labour MPs. A total of 322 Labour MPs nominated the Makerfield MP to become the next Labour leader on Thursday evening, far exceeding the required 81 nominations needed from the parliamentary party's 403 MPs.

Leadership candidates need 20 per cent of the party's MPs to nominate them, with a week-long nomination window ending on July 15. They also need to be nominated by at least three of the 31 socialist societies and trade unions affiliated to the party, or 5 per cent of the constituency Labour parties. Affiliate nominees must comprise at least 5 per cent of Labour's affiliated membership and include two unions.

With Burnham still the only declared candidate and having already secured overwhelming backing, a leadership contest appears unlikely. If only one candidate remains by July 16, when Parliament begins its summer recess, no contest will be declared and that person will become leader. Burnham could become Labour leader on July 17. He will only become prime minister once the constitutional handover takes place, which will more than likely occur on the next working day, July 20. Sir Keir Starmer will have to formally tender his resignation to the King at Buckingham Palace before the new leader is invited to form a new government.

Burnham, the former Greater Manchester mayor who recently won the Makerfield by-election, has outlined plans to set up a Number 10 in the north. Culture Secretary Lisa Nandy said an Andy Burnham government will be "faster and bolder" and will focus on "shifting the centre of gravity in the country so that all parts of the country are seen and heard and are able to contribute."

Despite widespread support, 78 Labour MPs did not publicly back Burnham, including Home Secretary Shabana Mahmood, John McDonnell, and Jess Phillips. Seven Welsh Labour MPs also withheld their endorsement. The new prime minister will have limited time to settle into the role before Parliament returns from its summer break in September.