Josckha Fischer, the veteran politician once synonymous with Germany's Greens, has bitterly attacked the party, warning it would face collapse if it returned to its left-wing pacifist roots.
The former German foreign minister was back in Berlin after an 18-month absence to publish his autobiography, The Red-Green Years, an account of his time in Gerhard Schröder's coalition government.
Mr Fischer, a guest professor at Princeton University, New Jersey, since leaving office at the end of 2005, has lost no time in criticising the Greens, which he helped found in the late Seventies. "There was a permanent battle between party and myself which has left wounds in its wake," he said.
Since losing power in 2005, the Greens have become a minor opposition party. In an attempt to regain a higher profile, the party has shifted leftwards and begun a heated debate about the country's military role in Afghanistan.
But Mr Fischer warned yesterday that the party would face "complete political collapse" if it continued on such a course. "If the Greens think they can restore their profile as a leftwing protest party without paying a heavy price, they are deluding themselves. Our support comes from the centre ground," he said.
Now approaching 60, Mr Fischer has given up nearly all the trappings of his Green roots. He has exchanged an anonymous flat in downtown Berlin for a villa in the affluent Grunewald district which he shares with Minnu, his 30-year-old Iranian-born wife and former student of politics.
For a politician who started out in the late Sixties as a radical Marxist not averse to fighting pitched battles with police, Mr Fischer has made a remarkable transformation: he spends much of his time writing commentaries or lecturing abroad on international affairs and has started a company called "Joschka Fischer Consulting" . Der Spiegel said yesterday that Green Party activists would probably be the last in the queue of those seeking his advice.
Yesterday Mr Fischer categorically ruled out a return to the hustings for the Greens. "I shan't be giving any more concerts," he said in a reference to his reputation as "the last live rock and roller in German politics". He said most of the party leaders seemed to be "delighted I am no longer there".
The first part of his book is a personal reckoning with the Greens and his time in power with Mr Schröder. He says he would have resigned as foreign minister had France and Russia not joined Germany in opposition to the Iraq war in 2002.
The autobiography devotes much space to Mr Fischer's battle to persuade the Greens to sign up to German support for the Nato bombardment of Serbia in 1999. The decision by the ruling coalition at the time, of Social Democrats and Greens, to support Nato broke with more than 40 years of post-Nazi era policy, which stipulated that the country should not engage in military operations beyond its borders.
Mr Fischer describes in detail how, at a Green Party conference in 1999, he was harangued by a mob of militant leftists and pacifists who temporarily deafened him by hurling a paint bomb at his head. He explains that, if his motion to support German involvement in Nato strikes had been defeated, he would have had to resign. This would have caused the country's first Red-Green administration to fall. "There would have been no point in going on any more," he conceded.
Mr Fischer's no-holds barred criticism of his own party came under attack yesterday from Jürgen Schreiber, his biographer. "The truth is that Fischer and the Greens were locked in a symbiotic relationship. Neither would have got as far as they have without the other," he said.Reuse content