Differences between Nick Clegg and David Cameron over Europe will emerge today when the Deputy Prime Minister will warn British Eurosceptics not to gloat over the crisis in the single currency.
Speaking in Paris, Mr Clegg will argue that the UK will lose influence in the European Union if it sits on the sidelines during the crisis afflicting the 17-member eurozone, and say that the Coalition Government should do more to help solve it.
Although Mr Clegg will not call directly for British taxpayers to prop up countries like Greece, some senior Liberal Democrats believe the UK should play a bigger role in future bailouts.
The Deputy Prime Minister will say: "There are problems in the eurozone and they are important, not just to members of the single currency, but to all Europeans. We may have different coins in our pockets, but our fates are intertwined."
He will rebuke Tory Eurosceptics and Labour MPs including Jack Straw who have expressed the hope that the euro will collapse under the strain of the crisis in Greece.
"A successful eurozone is essential for a prosperous UK. So there is no room for Schadenfreude here, no place for wagging fingers. Countries like the UK should not see ourselves as spectators, watching from the wings, triumphalist, complacent, as if Europe's economic woes are a eurozone problem, rather than a problem for all of us. As if it is enough to put your own house in order, but then stand by and let the neighbourhood crumble."
The Liberal Democrat leader will say: "On the one hand, some people, including senior members of the previous UK government, are predicting collapse and doing so with short-sighted relish, given it would do lasting damage to the UK economy. On the other hand, some people are now arguing that only complete fiscal union can work. It's not my role, or the role of the British government, to predict the future of a currency union we're not a part of, although I expect – as is usually the case – things will end up somewhere in between these extremes."
He will insist that Britain should be fully engaged in the efforts to save the euro so it can help to shape the structural reforms that Europe needs.
The speech will put Mr Clegg at odds with Mr Cameron, who yesterday described himself as a "sceptic" and raised the hopes of Tory MPs that he will seek to exploit the eurozone crisis to repatriate some powers from Brussels.
Such a policy was included in the Tory manifesto at last year's election but omitted from the Coalition Agreement after opposition from the Liberal Democrats, traditionally the most pro-European of the three main parties.
Mr Cameron told The Spectator magazine he believed the eurozone members would ensure its survival and predicted it would move "towards much more single economic government". In the negotiations on that inside the 27-member EU, he said, "there will be opportunities for Britain to maximise what we want in terms of our engagement with Europe".
The Prime Minister said he had already ensured that Britain could not be drawn into eurozone bailouts when a new mechanism takes effect in 2013.
Mr Clegg's aides played down the split last night, describing the former MEP as a "critical friend" rather than zealous supporter of the EU.
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