No British 'drawbridge' to stop Greek immigration, says Nick Clegg The crisis could spread quickly to other vulnerable countries such as Spain, Ireland and Portugal, which also have the single currency. Limits on migration within the European Union are allowed in "exceptional" circumstances. But Mr Clegg dismissed the idea that Britain might need to stop a rush of migrants taking advantage of free travel throughout the European Union. "I really do think some of the breathless talk in the media about do we pull up the drawbridge to stop hoards of people migrating across Europe is both far-fetched, somewhat apocalyptic in tone and deeply unhelpful," he told the BBC. We're not there yet. What I hope will happen is the Greek people will choose to stay in the eurozone, notwithstanding the sacrifices that involves, and there will be this new agreement to come up with a comprehensive solution to the eurozone. Despite efforts to calm fears about Greek immigration, Mr Clegg did warn of an "unravelling effect" if the country is allowed to leave the euro. "It was considered to be an irrevocable step - it couldn't be reversed," he said. Once you'd created this currency, it was there to stay. I think once that is proven not to be the case, if any individual country were to leave, the unravelling effect of that is almost impossible to predict. He also called for European politicians to put aside their differences and make a "grand bargain" to save the single currency. European leaders are still working on plans to stop Greece crashing out of the single currency, but the country's future largely rests on whether it manages to vote in a stable government at next month's elections. Last night, Lucas Papademos, the short-lived Greek prime minister who left office this month, warned that its public finances could collapse as early as next month, leaving salaries and pensions unpaid. The extremity of the situation was revealed by a Greek newspaper, which obtained a note from Mr Papademos to the country's president, Karolos Papoulias. "The state will face considerable difficulty covering its expenses in June," the document said.