Britain's Prime Minister David Cameron has warned businesses that the public support for the UK staying within the European Union is 'wafer thin'.

Speaking at the annual Confederation of Business Industry (CBI) conference, Cameron said that he could secure support for the UK to stay in the EU, despite overall public support for membership falling to new lows.

"It is my judgement that our current consent of remaining inside the EU is wafer-thin - we have not made the argument enough about why Europe matters," said Cameron in his CBI speech.

"I sit round that EU table ... and I can see this organisation is going to change. It is changing in front of our eyes because of the euro. Those countries that are in the euro, they need change to happen.

"We shouldn't stand in their way. But I think it is perfectly legitimate to say 'You, the eurozone members need these changes. Well, we outside the euro, we need some changes too'."

Political Parties Tussle Over EU Referendum

Cameron said there will be a referendum on the UK's membership of the EU in 2017 if his party is re-elected with a majority at the next general election.

Cameron called for the referendum after mounting pressure from his vociferous eurosceptic backbenchers, some of whom were beginning to doubt his leadership of the Conservatives

Britain's main opposition party Labour said at the conference that it is backing the coalition government and CBI's call for a renegotiated UK membership of the EU - though the party still refuses to put its support behind the proposed in/out referendum.

Meanwhile, the leader of the UK Independence Party launched a scathing attack on the CBI, after the business lobby group said that leaving the European Union would devastate the economy.

Nigel Farage said in a statement that the CBI's report, which was launched at its annual conference, is unrealistic and that leaving the bloc would not mean that Britain has completely turned its back on Europe.

"There is this deeply flawed view that leaving the EU would somehow mean a sudden end to trading with Europe," said Farage.

Cameron added at the conference that "we haven't made the argument enough about why Europe matters and frankly there are lots of things in the EU that badly need reform: it is too costly; it is not flexible enough; it doesn't help our competitiveness enough. It needs to change."