Cabinet tensions over David Cameron's decision to veto a European Union treaty have burst into the open as it emerged that Nick Clegg was privately furious with the Prime Minister.
Despite publicly backing Mr Cameron, the Liberal Democrat Deputy Prime Minister feels his actions were not in Britain's best interests and leaves the country isolated in Europe.
A source close to europhile Mr Clegg told The Independent on Sunday that the outcome of Thursday night's negotiations at the European Council in Brussels had been "a spectacular failure to deliver in the country's interest".
"Nick certainly doesn't think this is a good deal for Britain, for British jobs or British growth," the source said.
"It leaves us isolated in Europe and that is not in our national interest. Nick's fear is that we become the lonely man of Europe."
The source said Mr Clegg "couldn't believe it" when, on Friday morning, he was informed of the course of events and how Mr Cameron had sought to negotiate with fellow EU leaders.
The future of the coalition is already under scrutiny with Mr Cameron and Mr Clegg facing conflicting demands from their respective backbenchers in the wake of the dramatic veto.
Jubilant eurosceptic Tories have stepped up calls for a full renegotiation of Britain's position in the EU, only for Liberal Democrat deputy leader Simon Hughes to insist the issue was "not on the table" and that Conservatives should "calm down".
Lib Dem Business Secretary Vince Cable also expressed concern that Britain had "finished in a bad place" at the EU summit, where the 26 other nations embarked on a deal to save the euro without the involvement of the UK.
He told The Sunday Telegraph: "I am not criticising the Prime Minister personally. Our policy was a collective decision by the coalition. We finished in a bad place."Suggest a correction