British Prime Minister David Cameron. File picture: Suzanne Plunkett

London - Prime Minister David Cameron's plans to reshape Britain's ties with the European Union are in tatters after he failed to stop Jean-Claude Juncker becoming the next president of the European Commission, his main political rival said on Monday.

Cameron's loss of an unprecedented summit vote he forced over Juncker's nomination last Friday has sharpened concern that the world's sixth largest economy may be sliding towards the EU exit. Only Hungary sided with Britain in the 26-2 vote.

Ed Miliband, the leader of the opposition Labour party, said on Monday the vote represented an “utter humiliation” for the Conservative leader and that his failed strategy to block Juncker showed that his wider plans of renegotiating Britain's EU ties were in disarray.

“He couldn't get four countries to support him over Mr Juncker,” Miliband told parliament. “And if he can't get four countries to block the appointment of a president, how an earth is he going to get 27 countries to support a new (EU) treaty? ... His renegotiation strategy is in tatters.”

Cameron has promised to try to reshape Britain's EU ties if re-elected next year before giving Britons an in/out EU membership referendum in 2017.

Miliband said the “centre of gravity” of Cameron's party was drifting towards an EU exit, saying sarcastically that the British leader had given a master class in how to alienate EU allies by using threats, insults and being disengaged.