It is the former prime minister’s second intervention against Mr Corbyn, the frontrunner in the Labour leadership race.

Writing in the Observer, Mr Blair said he does not get the "Corbynmania" and denounced what he said is a “parallel reality” in which the Islington North MP’s supporters operate.

"In the Alice in Wonderland world this parallel reality has created, it is we who are backward looking for pointing out that the Corbyn programme is exactly what we fought and lost on 30 years ago, not him for having it," he said.

Mr Blair conceded that appeals from him and ex-leaders Gordon Brown and Neil Kinnock may be counter-productive and actually embolden Mr Corbyn’s supporters.

Still, Mr Blair said he felt like a veteran warning a young driver coming onto a dangerous road.

He insisted that evidence suggested that Ed Miliband had lost the May election because Labour "was considered anti-business and too left."

"Does this make any difference to the Corbynistas? Absolutely not," he said.

In what the Observer said was Mr Blair's final plea, the former prime minister said: "Someone… said to me: 'If you're writing something again, don't blah on about winning elections; it really offends them.'

"It would actually be quite funny if it weren’t tragic."

He likened the surge for Mr Corbyn to movements that had propelled the SNP to dominance in Scotland and helped Donald Trump emerge as a contender in the US presidential race, adding that the Labour Party was now "changed."

Andy Burnham, who is one of three people challenging Mr Corbyn for the leadership, responded to Mr Blair's words by telling Sky News: "Tony Blair won three General Elections for Labour.

"If we've got to a point now where the Labour Party says it doesn't want to listen to him I would think we've lost the plot.

"We've got to listen to people who have been there in the past and seen Labour when it had difficulties in times gone by."

Jennie Formby, political director of the Unite trade union, dismissed Mr Blair as a "neo-liberal multi-millionaire war-mongerer."

She tweeted: "He hasn't said anything constructive or useful so far re(garding the) leadership campaign, you can't just write off tens of thousands supporting JC."

Labour members, supporters and affiliates are currently voting in the Labour leadership race, with voting to close on 10 September.

The result is announced on 12 September.

Mr Corbyn remains the bookmakers' overwhelming favourite to pull off a shock win over experienced former cabinet ministers Mr Burnham and Yvette Cooper. Blairite candidate Liz Kendall is on course to finish a distant fourth.

In his previous intervention against Mr Corbyn, an old foe and vocal campaigner against the war in Iraq, Mr Blair said that a victory by Mr Corbyn in the leadership race would likely bring the "annihilation" of Labour.