Chancellor Gordon Brown and education and employment secretary David Blunkett, widely seen as successors to Tony Blair, will publish personal "manifestos" after the general election.

The move is unprecedented and will fuel speculation that Tony Blair will step down at some point during the next Parliament.

Gordon Brown's publication will be a "clear exposition" of his political philosophy, co-written with Lord Plant of Highfield, a Labour peer and former head of St Catherine's College, Oxford. David Blunkett is working on a book to be co-written with Tom Bentley, the director of think-tank Demos.