He also warned that leaving the European Union would be a "one-way ticket" with no option of return.

"Over the coming weeks, months and years, I will not rest until this debate is won -- for the future of my country, for the success of the European Union and the prosperity of our peoples for generations to come," he concluded.

Cameron promised a vote in the first half of the next parliament, if his party -- which is currently in a coalition government with the Liberal Democrats -- wins the general election due in 2015.

The prime minister has been under concerted pressure from some members of his party to hold a referendum on Europe. The so-called Eurosceptics want to see Britain get some powers back from the EU, as well as a reduction in legislation they say holds back businesses.

However, others both in and outside the party warn that creating uncertainty about Britain's membership in the European Union risks undermining the confidence of businesses and industry at a critical time.

Fellow European nations may also be unwilling to renegotiate the terms of Britain's membership.

France and others have made it clear that Cameron cannot "cherry-pick" which elements of the European Union he signs up to, or risk unraveling the union to suit British interests.

French Foreign Minister Laurent Fabius told radio station France Info that the planned referendum "risks being dangerous for Britain itself because Britain outside of Europe, that will be difficult."

If Britain did decide to leave the European Union, France would roll out the red carpet for business leaders, Fabius added.

Italian Prime Minister Mario Monti, speaking at the World Economic Forum in Davos, Switzerland, predicted Britain would remain in the EU.