European commentators have reacted with anger at Britain's decision not to join a tax and budget pact to tackle the eurozone debt crisis, though some are not surprised by the UK, which has stood for so long on the sidelines of the European project.
Many Germans are outraged by British Prime Minister David Cameron's move.
Alexander Graf Lambsdorff, head of the Germany's FDP group, part of the European Liberals, goes as far as to say it was "a mistake to let the British into the EU".
Britain must now renegotiate its relationship with the EU, he said. "Either they [the British] do it on their own initiative, or the EU refounds itself - without Great Britain. Switzerland is a model towards which Britain can turn itself."
Others see the summit's outcome as merely revealing faultlines and deep differences in attitudes towards Europe.
Writing in the Italian La Repubblica newspaper, Alessio Sgherza says that the summit "sank... because of the old but still unresolved division between... pro-European and Eurosceptic states".
Meanwhile Daniel Cohen-Bendit, joint leader of the Greens in the European Parliament has labelled Mr Cameron "a weakling".
German Christian Democrat MEP Elmar Brok, foreign policy spokesman for the centre-right in the European parliament, echoed his sentiment: "If you're not ready to abide by the rules, you'd do better to keep your mouth shut."
Yvan Duvant, writing to the BBC from Olargues, in France, says that as the UK is slowing down the move towards EU integration, it should leave the union altogether: "What's the point of keeping this country in the EU? The British people should put pressure on their government to quit. Maybe the British would do better without the EU. Europe will definitely do better without the UK."