The Labour Party's ruling national executive has announced that a new leader will be named on 17 July if only one candidate comes forward. If a rival secures the backing of 81 Labour MPs, the party will hold a full leadership election and declare the result on 29 August.
The choice of chancellor is already drawing fire, with the next occupant of No 11 expected to shape everything from the autumn Budget to the future ownership of Britain's utilities. Business owners are watching closely as the identity of the next occupant of No 11 will have direct consequences for investors and the wider business community.
The two leading contenders, Wes Streeting and Ed Miliband, hail from different wings of the party and would almost certainly pursue different priorities. Streeting, a Blairite, is regarded as the more business-friendly option and the candidate most likely to reassure international investors.
However, some on the left worry he would be lukewarm on returning water and energy companies to public ownership. Miliband, on the other hand, is seen as more ideologically aligned with the programme of prospective prime minister Andy Burnham, but has drawn anger from sections of both the unions and the business community over his approach to net zero.
Unions with a strong presence in the North Sea oil industry have been exasperated by Miliband's refusal to soften his pledge not to issue new exploration licences. They also fear he will decline to approve the Jackdaw and Rosebank megafields, even though waving them through would not technically breach that promise.
Unison, Britain's largest trade union, has thrown its weight behind Miliband, citing the need for a chancellor who will rewire the economy and properly invest to improve the lives of the majority. The union's endorsement will strengthen Miliband's standing within the Labour movement.
Other possible candidates for the chancellor position include Shabana Mahmood, the home secretary, Yvette Cooper, the foreign secretary, Pat McFadden, the work and pensions secretary, John Healey, the former defence secretary, and Jonathan Reynolds, the chief whip.
The new prime minister's first appointment has already drawn fire, with Burnham choosing his former cabinet colleague and long-standing friend James Purnell as chief of staff. Purnell's Blairite pedigree has irritated parts of the Labour left.
Burnham is assembling his inner circle of advisers and ministers, having entered the Commons only a week ago. The former Greater Manchester mayor will set out his thinking on devolution and the economy in Manchester on Monday, but he is under mounting pressure to name his chancellor.
The choice of chancellor is a historic opportunity for Burnham to rebuild the country in the interests of workers and communities, but a decision that is also fraught with complexity. Business owners are watching closely as the identity of the next occupant of No 11 will shape everything from the autumn Budget to the future ownership of Britain's utilities.
