David Cameron heckled by anti-EU protesters during key business speech

The Prime Minister was interrupted during his address to the Confederation of British Industry about his EU renegotiation effort

David Cameron has been heckled by anti-EU protesters as he gave a key speech to business leaders on his bid to renegotiate Britain's membership of the European Union.

He was forced to pause his off-the-cuff speech to the Confederation of British Industry (CBI) as protesters in the audience chanted "CBI, voice of Brussels".

The Prime Minister told them to "stop making fools of yourselves" and said they could ask a question if they "sit down".

Protesters lined the streets outside the CBI conference venue, being held at the Grosvenor House Hotel on Park Lane in central London.

The pair of protesters inside the conference hall were targeting the CBI's pro-buisness stance rather than attacking Mr Cameron, who has refused to rule out leading the campaign to leave the EU if European leaders refuse to grant him key concessions in his bid to reform Britain's membership of the EU.

He insisted he had "no emotional attachment" to the institutions of the EU and said he wanted to "debunk" the argument put forward by pro-EU supporters who claim the UK could not survive outside the union. "I don't think that is true," he said.

However he pledged to throw himself "headlong into keeping Britain in a reformed Europe" his bid to renegotiation terms of membership succeeds.

On Tuesday he will set out his list of official demands in a letter to the President of the European Council, Donald Tusk.