Tony Blair yesterday warned Labour supporters to reject the “Alice in Wonderland” appeal of Jeremy Corbyn or risk driving the party into an abyss.

In defiance of appeals from the left-winger’s leadership rivals to resist further interventions, he issued a fresh warning the party would become unelectable.

Writing in The Observer, the former prime minister conceded that appeals from himself and ex-leaders Gordon Brown and Neil Kinnock appeared only to have emboldened those who have propelled the veteran MP from rank outsider to frontrunner to succeed Ed Miliband.

He accepted that he had as yet failed to understand the “powerful” phenomenon behind the serial rebel’s popularity or how best to respond to it. But he mocked those behind it for embracing a “politics of parallel reality... in which reason is an irritation, evidence a distraction, emotional impact is king and the only thing that counts is feeling good about it all”.

With less than two weeks until the result of the election is announced, Corbyn remains the bookmakers’ overwhelming favourite to pull off a shock win over experienced former cabinet ministers Andy Burnham and Yvette Cooper.

Liz Kendall, the most Blairite of the candidates, is on course to finish a distant fourth.

Stark warnings from Blair – who previously said people whose heart was with Corbyn should “get a transplant” – have done nothing to dent the left-winger’s shock lead and have been attacked as unhelpful by his mainstream rivals.

An angry Blair – who made significant reforms to the party and led it to three consecutive general election victories – insisted that it was important to speak out to prevent the party repeating past mistakes.

All the evidence showed Labour lost the 2015 election because it was “anti-business and too left” and had no credible economic plan, he said.

Don’t go any further, we have been up and down this road many times and we’re warning you

“Neil Kinnock, Gordon Brown and I have collectively around 150 years of Labour party membership. We’re very different. We disagree on certain things. But on this we’re agreed,” he wrote.

“Anyone listening? Nope. In fact, the opposite. It actually makes them more likely to support him. It is like a driver coming to a roadblock on a road they’ve never travelled before and three grizzled veterans say: ‘Don’t go any further, we have been up and down this road many times and we’re warning you there are falling rocks, mudslides, dangerous hairpin bends and then a sheer drop’.

Labour leadership contender Jeremy Corbyn speaking outside Tudor Square in Sheffield yesterday. Photo: PA WireLabour leadership contender Jeremy Corbyn speaking outside Tudor Square in Sheffield yesterday. Photo: PA Wire

“And the driver says: ‘Screw you, stop patronising me. I know what I’m doing.’

“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.”

Blair said he had been urged not to “blah on about winning elections; it really offends them”, adding: “It would actually be quite funny if it weren’t tragic.”

He likened the surge for Corbyn to movements that had propelled the Scottish National Party to dominance in Scotland, fuelled the re-emergence of Marine Le Pen’s far-right National Front in France and helped Donald Trump and Bernie Sanders emerge as contenders in the US presidential race.

“They’re making all those ‘in authority’ feel their anger and their power.”

Burnham, who previously criticised Mr Blair for making “dire predictions” of the consequences of victory for Mr Corbyn, said Labour would be mad not to listen now to the former prime minister.

“Tony Blair won three general elections for Labour. If we have got to a point now where the Labour Party says it doesn’t want to listen to him then I would think we have lost the plot,” he told the Murnaghan show on Sky News.

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