GMB leader Paul Kenny blasted Blairite “nostalgia” for New Labour yesterday as he urged leadership candidates not to take the party back two decades.

Mr Kenny, chair of the Unions Together group that represents Labour’s 14 affiliates, said Labour returning to the politics of a “bygone age” would not help it win the 2020 election.

He said: “If the Labour Party acts in haste it will repent at leisure.