Published by Mark AckroydBritish forex dealers working in London may be concerned about the possibility of the city's financial sector becoming ostracised from the rest of Europe.That scenario is very much on the cards, according to views expressed by deputy prime minister Nick Clegg this weekend.Speaking to the BBC's Andrew Marr programme, the Liberal Democrat leader said coalition partner and prime minister David Cameron was wrong to last week declare Britain is refusing to sign up to a new European Union treaty.The Conservative leader blocked changes to the Lisbon Treaty during an EU summit in Brussels on Friday (December 9th).Mr Clegg believes that could come back to haunt the UK, as the country becomes one that no longer matters to the rest of the continent."I'm bitterly disappointed by the outcome of last week's summit, precisely because I think now there is a danger that the UK will be isolated and marginalised within the EU," he stated.Mr Clegg added: "I don't think that's good for jobs, in the City or elsewhere. I don't think it's good for growth or for families up and down the country."The prime minister said he refused to back the deal as it failed to offer safeguards over the UK's financial sector, including forex markets.But he will be accused today by Labour leader Ed Miliband of failing in his objective to protect these industries, which are crucial to the British economy, the BBC noted.Mr Cameron is due to face the House of Commons this afternoon to explain his decision and is likely to come under fire from both Labour and the Liberal Democrats, with the topic of the impact on financial markets set to feature.New Italian prime minister Mario Monti recently said that Europe must work together to overcome its financial crisis, as the collapse of Italy would almost certainly mean the end for the euro.For more information on foreign exchange treasury services and risk management, visit our Corporate FX site