By Caroline Wyatt
BBC News, Paris
Former French President Valery Giscard d'Estaing has strongly defended the EU constitution that he created.
Mr Giscard d'Estaing believes most French will vote Yes
Mr Giscard d'Estaing said it could not be renegotiated if the French rejected it in their referendum on 29 May.
He said the ratifications of the treaty across Europe, including the UK's own planned plebiscite, would continue, even in the face of a French No.
Opinion polls in France show the No vote slightly ahead, with just a week and a half to go.
Mr Giscard d'Estaing robustly defended his creation - the European constitutional treaty he spent several years negotiating.
He dismissed the idea of renegotiation, saying "it would be a useless and non-productive confrontation".
"There is no opening for that. What do you want to renegotiate? We had a long negotiation, then inter-governmental negotiation for one full year."
He said the No campaigners in France were attacking from the extremes of left and right.
But he insisted the treaty neither handed too much power to Brussels nor threatened the French social model. "The states remain, and we keep our citizenship."
The former French president admitted the referendum came at a bad time for France.
Unemployment is running at 10%, putting the French people into what he calls a negative mood.
As for Turkish membership of the union, an issue which has become entangled with the debate over the constitution in France, Mr D'Estaing said that although an important neighbour, Turkey could never become a member of the European political system.
"Turkey cannot be a member of the European political system. Why? It will be the most numerous... and poorest, so all the funds will go to Turkey."
Mr D'Estaing said he believed that in the end, the French would look to their consciences and vote Yes to the constitution - albeit by a narrow majority of around 52% or 53%.
With a Yes vote, he said, "people will be pleased, because they don't want to enter into an adventure... They have a sense of responsibility."