PARIS, May 29 (Xinhuanet) -- France holds a referendum on the new constitution of the European Union (EU) on Sunday with opinion polls pointing to a "no" vote.

    About 42 million eligible French voters are expected to cast their ballots in 64,700 polling stations all over the country. French and EU leaders will be watching anxiously. The polling stations open at 8 a.m. local time (0600 GMT).

    The latest opinion polls put the "no" camp clearly ahead with up to 56 percent of the voters expected to vote against the treatyat the end of a heated campaign that divided France and became a debate on the government's economic record and the future of Europe.

    Analysts say a "no" vote could trigger a political upheaval in France, a main founding member of the EU, and a domino effect of rejections from more EU members.

    The fear that a French rejection of the EU constitution would also weaken the country's president and lead to the ouster of the prime minister and a division within the ruling party.

    Analysts also widely agreed that the 25-nation EU will plunge into an unprecedented crisis if the French get cold feet about greater political integration with other Europeans.

    For French President Jacques Chirac, who opted to refer the constitution to a referendum and backed it with all authority of his office, a "no" vote would hobble the last two years of his presidency and make his third term in office almost impossible.

    As a result of a likely defeat for the constitution, Chirac is expected to fire his unpopular Prime Minister Jean-Pierre Raffarin,with Interior Minister Dominique de Villepin or Defense Minister Michele Alliot-Marie being his possible successor.

    Chirac, who has staked his prestige on the approval of the constitution, has warned voters that a "no" vote would diminish the country's role in Europe and make it the "black sheep" on the continent.

    Other EU members feared that a "no" vote in France would unleash a domino effect across Europe, influencing voters in the Netherlands, Poland, Denmark and Britain to say "no" in future referendums on the constitution.

    The constitution, signed by EU leaders last October in Rome, sets rules for the EU that are intended to make decision-making easier after the bloc's enlargement from 15 to 25 member states inMay 2004.

    The constitution requires the approval of all the 25 EU membersto go into force. On Friday, Germany became the ninth EU member toratify the treaty after Austria, Greece, Hungary, Italy, Lithuania,Slovakia, Slovenia and Spain. Enditem