- EU Commissioner Olli Rehn says UK need not "threaten" to leave European Union
- Rehn: "It is only to the mutual benefit of Britain and Europe that Britain stays as a member"
- UK Prime Minister David Cameron has pledged to hold a referendum on membership
- Rehn said threat of the breakup of the euro "has all but disappeared"
A top European Union official says there's no need for Britain to make threats to leave the union in order to reform its membership.
"In my mind it is only to the mutual benefit of Britain and Europe that Britain stays as a member of the European Union," EU Economic and Monetary Affairs Commissioner Olli Rehn told CNN's Richard Quest.
British Prime Minister David Cameron sparked the debate in a speech Wednesday in which he promised the British people a vote on European Union membership if he wins the next general election in 2015.
"But as I was listening to the speech of Prime Minister Cameron yesterday concerning his policy agenda there are in fact many issues I can agree with and the commission is already working for those including how to increase the competency of European industry, how to complete the single market, how to pursue free trade agreements," Rehn said.
"That's all fine ... we work for common interest and growth of Europe. But you don't have to make threats of leaving the union to have a debate on those."
Cameron told CNN's Christiane Amanpour that he has no regrets over the referendum promise, despite unhappiness among some European partners.
"It's really important that we've set out a plan for how we get change in Europe that will benefit all of Europe, making it more open, more competitive, more flexible, and how we secure Britain's place within that," he said.
The European Union is already changing to meet the needs of the 17 members who are part of the euro single currency, Cameron said. Britain is not in that group.
On the eurozone debt crisis, Rehn said the risk of the breakup of the euro "has all but disappeared thanks to the actions taken by the member states and not least by the European Central Bank.
"However, of course, in the real economy we have a very difficult situation in many countries -- high unemployment, low growth -- and we have to use the better sentiment in the markets and restoration of confidence to bolster growth and job creation," Rehn said. "That's the focus of 2013."