It includes a "balanced budget rule" that requires governments to keep deficits below 0.5% of gross domestic product, among other things.

CNN: Ireland's voters approve European fiscal treaty

Should he refuse to adopt a balanced-budget rule it is hard to imagine Mrs Merkel taking him to court.

ECONOMIST: Charlemagne

Although the Socialists opposed Mr Sarkozy's plan to adopt a balanced-budget amendment in the constitution, Mr Hollande promises to pass a golden rule of his own (as an ordinary law).

ECONOMIST: Charlemagne