EU chief claims exit would leave UK with 'zero' influence

David Cameron's influence as Prime Minister would be "zero" if Britain left the European Union, the outgoing president of the European Commission has claimed.

Jose Manuel Barroso said Britain's departure from the EU would be "negative" for all parties, as he urged the UK to engage in "constructive dialogue" on the issue.

Mr Cameron, who has promised to give the British people an in-out referendum on the EU if the Conservatives win the next election, last week vowed to have "one last go" at negotiating.

"What would be the influence of the Prime Minister of Britain if he was not part of the European Union? His influence would be zero," Mr Barroso told BBC's Andrew Marr Show.

"He [David Cameron] knows well that without the EU, Britain will have less influence," he said.

Jose Manuel Barroso said Britain will have less influence if it decides to leave the EU. Credit: BBC/Andrew Marr Show

The Prime Minister claimed action was needed to give the UK more "effective control of migration".

But Barroso hinted that the fundamental principle of free movement of people within the EU was non-negotiable, and disputed claims Britain had a problem with immigration.

Any caps on migration from the EU would be in breach of European laws, Barroso added.

He also criticised Foreign Secretary Philip Hammond for saying Britain was "lighting a fire under the European Union" by holding a referendum.

"I'm told the Foreign Secretary was the former minister of defence. I think this reference to fire and weapons is more appropriate for defence than foreign secretary," Barroso said.