Voting has ended in a French referendum on the new European Union constitution that is being watched across Europe.
Results are expected late on Sunday or early on Monday
Exit polls are expected shortly. Officials say turnout appears to be much higher than in France's previous European referendum, held in 1992.
It is the first binding public ballot on the EU constitution, which must be ratified by all 25 member states to become law.
The issue has polarised France and the vote is expected to be close.
Correspondents say a French "Yes" could give the pact new momentum but a "No" may trigger more opposition and threaten the EU's first constitution.
Nine countries have so far ratified the constitution, which aims to streamline EU decision-making.
The outcome in France is being given extra importance because, as one of the architects of the EU and a key power in the organisation, it is traditionally a leader in the bloc.
Officials said 66% of voters had cast their ballots by 1700 GMT - three hours before the last polling stations closed.
That was nearly 10 points more than turnout registered at the same time of the day during the 1992 referendum on the Maastricht Treaty
Opinion polls have given the "No" camp a narrow lead, but the government hoped the 20% or more of undecided voters would opt for a "Yes" at the last minute.
The campaign has reflected strong divisions between those who say the constitution will ensure France's influence at the heart of Europe and critics who argue it will undermine the country's ability to protect jobs, wages and living conditions.
The governing centre-right UMP party and the opposition Socialists have urged voters to support the proposed constitution.
But leading Socialist dissenters joined Communists and union leaders to press for a "No". Far-right parties also reject the proposed constitution.
The BBC's William Horsley in Paris says the debate has engaged the nation on European issues - including economic policy and immigration - in a way rarely seen before.
He says the result - expected late on Sunday or early on Monday - is awaited with both anxiety and anticipation across France and the EU.
President Chirac and his wife were among the 25% who voted early
For one day, French citizens hold the immediate future of the union in their hands, he says.
Voters in French Guiana, the Caribbean islands of Martinique and Guadeloupe, French Polynesia and Saint-Pierre-et-Miquelon off Canada cast their ballots a day earlier.
Results from the overseas departments and territories will not be revealed until after polls have closed in Paris and Lyon at 2000 GMT.
The constitution was finalised last year after long and difficult negotiations among EU governments.
The treaty includes a Charter of Fundamental Rights and the creation of a foreign minister and a diplomatic service.
Member states can ratify the document through a referendum or by parliamentary vote.
Germany ratified the charter on Friday, with an upper house vote timed to boost France's struggling "Yes" camp.
Those who want the treaty rejected are thought to be ahead in the Netherlands, which will hold its referendum on Wednesday.