IF THE French public votes “no” on May 29, the EU constitution will be dead in its present form, and there will be no British referendum. That is clear, but it is the only clear point.

The fuss of the past 48 hours about whether or not there will be a British referendum is largely nonsense. There is no confusion. Jack Straw has to say there will be a referendum here “as long as there is a treaty”. First, no minister can hypothesise publicly about might happen if France votes “no”. That would undermine the chances of a “yes” vote.

Secondly, note the key qualification “as long as there is a treaty”. A French “no” would lead to an EU summit next month under the Luxembourg presidency when the existing treaty would be pronounced dead.

An even more complicated scenario might be if the French narrowly voted “yes”, but the Dutch voted “no” three days later. That would not kill the treaty, but it would create nightmares for countries still to ratify it, such as Britain.

There is no chance of a repeat of the renegotiations that led to successful second referendums after voters in Denmark and Ireland had rejected earlier treaties in 1992 and 2001. As the Centre for European Reform points out, French opposition, especially on the Left, is fuelled mainly by fears about the direction of the EU, rather than by the treaty itself. So it would be impossible to meet French objections by creating opt-outs or special provisions, as in the Danish or Irish cases.

What happens depends largely on President Chirac. Does he say the treaty was lost because it favoured the British liberal market model, the reverse of the “no” case here? France might then seek to revive a core Europe with closer integration and greater social protection, along with Germany, Spain and Belgium.

Alternatively there could be an attempt to save parts of the treaty, via a minimal agreement covering the powers of EU institutions. But would this require just parliamentary ratification, or a referendum, as Eurosceptics would argue? Either option would create negotiating headaches for the British Government as it takes over the EU presidency in July.

The best hope for Britain might be an informal agreement on provisions not requiring treaty changes such as having presidencies of EU councils lasting for longer than six months. If France and the Dutch vote “yes” in their referendums, the pressure will then be on Britain, though there could be close results in Poland and Denmark in September.

The Bill to approve the treaty and to establish a referendum is being introduced next week, but will not be debated until after the French and Dutch votes. Although the Bill will have a rough parliamentary passage, it will go through and the key question is the date of the referendum.

Liam Fox, the Shadow Foreign Secretary, suggested October 13, but it is likely to be next spring or early summer.

Winning a referendum is the hardest task facing Mr Blair in the rest of his premiership. This is not impossible, but it will be very tricky as long as it can be presented as a vote on whether Mr Blair stays or goes. But a “no” vote is not in Gordon Brown’s interests since the last thing he wants is a fraught negotiation over Britain’s relations with the EU.

There are no easy options for Britain: only varying shades of difficulty.

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