Andy Burnham has vowed to renationalise Britain's railway network "line-by-line" if he becomes prime minister.
The Labour leadership hopeful said he wanted to put "passengers before profit" by taking the railways back into public ownership.
Mr Burnham is seeking to claw back ground from Labour leadership frontrunner Jeremy Corbyn, who has built up significant momentum in the race to replace Ed Miliband, who resigned in the wake of the party's heavy defeat in May's election.
Mr Burnham's campaign manifesto will outline plans for a establishment of a new "national rail" government body.
We need a new approach to our railways, one that puts passengers before profit.
Burnham - who is up against Corbyn, Yvette Cooper and Liz Kendall - will find out if he has won the Labour leadership at a special conference on September 12.