Labour risks becoming a “third party” in the Commons if it fails to drop Jeremy Corbyn’s brand of politics before the next election, two former ministers have warned.

Andy Burnham, the mayor of Greater Manchester and former health secretary, said Labour was on course to become a “shrunken political party” or “red version of the Liberal Democrats” unless it returned to “credible” policies that appeal to working class voters.

Frank Field, the former welfare minister, separately claimed that if Mr Corbyn is succeeded by another hard-left leader, "Labour’s representation in Parliament will collapse."

Both centrist former Labour ministers were speaking in interviews on LBC with Liam Halligan, the Telegraph columnist, due to be broadcast on Sunday morning.

Mr Burnham, who is said to be backing the backbencher Lisa Nandy as a potential successor to Mr Corbyn, said he had been “heartbroken” to see the Greater Manchester seat that he represented for 16 years vote for a Conservative candidate for the first time since 1922.

But he added: “You could see it coming. This is the London-centric nature of the Labour party, that’s been going on for a long time. In recent years, Labour has been speaking to the liberal, university educated left, not it’s working class side. I’m afraid this result reflects that.”