Tony Blair: Labour must avoid 'traditional leftist' platform
The intervention came as a public poll for the Times by YouGov showed hard-left candidate Jeremy Corbyn ahead in the Labour leadership race.
Mr Blair was scathing about Mr Corbyn's campaign, saying: "If your heart is with Corbyn, get a transplant."
He suggested “radical leftism” could be “quite reactionary” compared with “radical social democracy, which is all about ensuring that the values are put to work in the most effective way, not for the world of yesterday but for today and the future”.
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Mr Blair said he did not want to explain how to win elections, although he noted that “you win from the centre... you don't win from a traditional leftist platform”.
“I wouldn't want to win on an old fashioned leftist platform – even if it was the route to victory, I wouldn't take it,” he said, in a speech to the think tank Progress.
He argued that 2015 was not 2007 or 1997, “so yes move on, but don't for heaven's sake move back”.
“If we do then the public won't vote for us, not because our thoughts are too pure but because our thoughts are out of touch with the world they live in today.”
Mr Blair advised the Labour party to take a five pronged approach to rebuilding support, which he said was an “exciting and not a depressing challenge”.
He said the party should think about “real” policy, and regain economic credibility.
“There is absolutely no case whatsoever for effectively accepting that Labour caused the crash, but we cannot address the future unless we are clear about the past and unless we show we are completely confident in the sphere of economic policy” he argued.
It should also learn from “forward thinking” Labour councils, have a dialogue with business and work out what a “political organisation looks like in today's world”, including how it makes decisions, communicates and organises, he argued.
“Labour shouldn't despair. We can win again. We can win again next time. But only if our comfort zone is the future and our values are our guide and not a distraction,” he added.
UKIP & SNP
Mr Blair also said the SNP and Ukip had “clouded” Labour's direction because they “seem to have pointed away from the centre”.
“The answer to the problems of Scotland is no more about being more Scottish and leaving the UK than the answer to the problems of England is being more English and getting out of Europe and blaming immigrants.”
He argued such arguments should be taken “head on”.