José Manuel Barroso was left fighting for his job as head of the European Commission last night after MEPs snubbed EU leaders and refused to endorse him for a second term.

The Portuguese conservative should have been a shoo-in after winning unanimous backing from the 27 member states but the heads of the Socialist, Liberal and Green MEPs blocked plans for a vote next week in Strasbourg to agree his re-appointment.

The impasse leaves Mr Barroso to sweat about his future over the summer and risks making him and the EU seem a lame duck on the eve of the G8 and in preparations for the Copenhagen climate change talks.

Mr Barroso’s mandate ends on October 31 and his supporters are exasperated because they can see his re-appointment dragging on for months while MEPs attempt to extract maximum concessions from the member states and European Commission.

Mr Barroso — who is strongly supported by Britain and was appointed in 2004 thanks largely to Tony Blair — is caught in a trial of strength as MEPs test their powers to resist pressure from EU governments.

He is also the victim of internal jockeying in the European Parliament, where the centre-Right emerged as the big winner of last month’s elections, but does not have the strength to force a vote against the rest of the chamber despite support from the new Tory group.

MEPs will now seek to use his re-appointment as a bargaining chip when it comes to filling the two new jobs of EU foreign minister and President of the European Council set to be created by the Lisbon Treaty, should it pass a second referendum in Ireland in the autumn.

European Socialists, reduced in numbers from 214 to 183 MEPs, are demanding a work programme from Mr Barroso that will include more measures to protect jobs and help the unemployed, rather than what they see as his obsession with open markets and competition.

Martin Schulz, the German MEP who leads the Socialist group, criticised EU governments for trying to foist Mr Barroso on the new Parliament at its first session.

“This is a failure for the European Council because it was not prepared to take note that there was no majority in Parliament for a vote now,” said Mr Schulz. “It is a major blow to Mr Barroso, who has chosen completely the wrong strategy. Instead of looking for a majority to renew the European Union with more social development, he has sought only a majority for himself.”

Mr Barroso insisted that he remained calm about the setback, despite reports that Angela Merkel, the German Chancellor, was fed up with his lobbying behind the scenes.

“I am very relaxed,” he said. “When the parliament is ready, I’ll be ready. My name was the only name publicly mentioned before the European parliament elections. After that, I got the unanimous support of EU heads of state and government.”

The leader of the Green MEPs, Daniel Cohn-Bendit, tonight proposed several names he said would be "much better than Barroso" although none has put themselves forward. They included Mary Robinson, the former Irish President; Chris Patten, the former British commissioner; Guy Verhofstadt, the leader of the Liberal MEPs; and Francois Fillon, the French Prime Minister.

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