Davos , Switzerland ( CNN ) -- 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 do n'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 . ''
European Union Commissioner David Cameron says UK need not `` threaten '' to leave European Union . Rehn : `` It is only to the mutual benefit of Britain and Europe that UK stays as a member '' Britain Prime Minister Olli Rehn has pledged to hold a referendum on membership . Rehn said threat of the breakup of the euro `` has all but disappeared ''