The Irish 'no' to the Lisbon treaty delivered a grave blow to Nicolas Sarkozy, who had big ambitions to put a French mark on a re-launched European Union when France takes over the six-month rotating presidency next month.

The French President struggled to put a brave face on the defeat, issuing a joint call with Chancellor Angela Merkel of Germany for remaining EU states to continue ratifying the treaty that both pushed through together in June last year.

"We take note of the democratic decision of the Irish citizens with all due respect, even though we regret it," they said. "We are convinced that reforms contained in the Lisbon Treaty are necessary to make Europe more democratic and more efficient and that they will allow it to confront the challenges facing its citizens," they added.

Jean-Pierre Jouyet, France's Europe Minister, expanded on French disappointment. "This is an incident. We are saddened, we are mostly saddened for our Irish friends but we will go forward," he said.

The rejection leaves the French President to pick up the pieces after the failure of the "mini-treaty" which he helped broker as soon as he took office last year following France's 'no' to the Constitution in 2005.

Publicly, the Elysee Palace is putting the best face possible on what amounts to a disaster for the Franco-German effort to get the Union's new streamlined institutions into place. It means that France will no longer be the main broker in the appointment of a new semi-permanent president and foreign minister for the post-treaty union, which was supposed to open on July 1.

Bernard Kouchner, the Foreign Minister, said this morning that an Irish no would not prevent France from pushing ahead with all its other plans to forge new EU approaches to the energy crisis, climate change, immigration policy and other matters. Dr Kouchner had, however, taken a strong line in publicly warning Ireland that a "no" vote would be a heavy blow to Europe.

Much of Mr Sarkozy's turn in the EU chair will now be spent on planning how to pick up the pieces. The most discussed option is an attempt to re-present the treaty, possibly in modified form, for adoption by Ireland. The method worked the last time, when Ireland rejected the 2000 treaty of Nice. But French diplomats are sceptical that this can be done this time.

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