British Finance Minister George Osborne appealed to Germany yesterday to ensure eurozone decisions and costs are not imposed on Britain in exchange for help making the single currency union stronger.

Mr Osborne, seen as the frontrunner to succeed Prime Minister David Cameron, is leading a new round of talks in European capitals, keen to sell Britain’s proposals for reform while keeping vocal eurosceptics in his own party at bay before a referendum on membership of the bloc by the end of 2017.

Speaking to government and business leaders in Berlin, Mr Osborne outlined what he said were “the changes we need to stay in the European Union”.

“Let me be candid: there is a deal to be done and we can work together,” he said at an event sponsored by the Federation of German Industry (BDI).

“Rather than stand in your way and veto the treaty amendments required, we in Britain can support you in the eurozone make the lasting changes that you need to see to strengthen the euro.

You get a stronger euro. We make sure that the voice of the pound is heard when it should be

“In return, you can help us make the changes we need to safeguard the interests of those economies who are not in the eurozone,” he said.

With UK opinion polls showing a narrowing of support for staying in the EU, Mr Cameron’s government is under increasing pressure to take on eurosceptics in both his ruling Conservative Party and the opposition Labour camp directly.

Nigel Farage, leader of the anti-EU UK Independence Party (Ukip), described Mr Osborne’s speech as “sycophancy” and said it sounded “more like a speech from an EU Commissioner”.

Mr Osborne has made protection for states in the EU but outside the 19-member single currency area a priority for the renegotiation to defend Britain’s financial services which account for about eight per cent of its economy. Setting out the deal he proposed making with Germany and other eurozone countries, Mr Osborne said the “inexorable logic”of monetary union would mean the EU’s treaties would have to be changed to support closer economic union between its members.

“When it comes to the relationship between those who use the euro and those who do not, here is the deal: you get a eurozone that works better, we get a guarantee that eurozone decisions and costs are not imposed on us,” he said.

“You get a stronger euro. We make sure that the voice of the pound is heard when it should be. A deal that is written into law, a deal that is good for Britain and a deal that is good for Germany too. The result will be a better European Union.”

Mr Cameron launched his most open defence to date of Britain staying in the EU last week by telling eurosceptics the country should not try to emulate outsider Norway which pays the same amount to the bloc but is not a member.