PARIS, Nov 28 (AFP) - Nicolas Sarkozy, France's ambitious finance minister, moved one step closer to his dream of succeeding Jacques Chirac as French president on Sunday when the ruling conservative party formally named him its leader.

The position, which will require Sarkozy to give up his government portfolio, is widely seen as a springboard for 2007 presidential elections that Chirac may or may not contest.

A rally in the Paris suburb of Le Bourget confirmed Sarkozy's new role as chief of the Union for a Popular Movement started by Chirac.

French media have only half-jokingly called the moment a "coronation" in reference to its lavish spectacle and to the aspirations of 49-year-old Sarkozy, who is easily the country's most popular politician.

According to reports Sunday, Sarkozy won 85 percent of the ballots cast by the UMP's 120,000 members, around a quarter of whom were attending the rally in a vast trade hall decked out in the TV-friendly style of US party conventions.

Prime Minister Jean-Pierre Raffarin and Interior Minister Dominique de Villepin were among the ministers taking part. Chirac, though, was not present and sent his wife Bernadette instead.

During his two and a half years in government, first as interior minister then as finance minister, Sarkozy - or "Sarko" as he has been dubbed - embarked on an energetic campaign of reforms that seemed more designed to keep his profile high than to advance any underlying principles.

He has been called, in a semi-derogatory tone, "Mr America" for his dynamic approach to first cracking down on crime and then cracking down on the country's deficit while courting maximum media exposure.

But he has also brandished protectionist credentials, notably when he recently pushed France's big supermarket chains to cut grocery prices and intervened to make sure French companies did not fall under foreign control.

That blend of opportunism and populism recalls Chirac's own style, although the diminutive Sarkozy, the son of a Hungarian immigrant, is perceived as brasher than the current president.

Chirac, now the elder statesman of European politics, turns 72 on Monday, the same day Sarkozy is expected to hand in his resignation as finance minister, and has not said whether he will stand for a third term in 2007.

If he does, it is possible he would have a showdown with Sarkozy, who earlier this year said he thought about the presidency and "not just when I'm shaving".

That has raised fears of a bitter internecine conflict in the UMP, which has suffered a series of electoral defeats in the past two years.

Chirac's dislike of Sarkozy has been as naked as the latter's ambition.

The president shuffled Sarkozy around the government in a vain bid to sap his rising popularity and then told Sarkozy that he would have to give up his ministerial post if he became UMP chief.

Chirac's own preferred successor, loyal technocrat and former prime minister Alain Juppe, was forced to give up the UMP leadership after being convicted of illegal party financing.

Juppe appealed the sentence, which brings a disqualification from public office, but regardless of the verdict, expected Wednesday, has already stepped down from most of his various functions.

De Villepin, the handsome and erudite aristocrat who shot to international fame for his speeches while foreign minister against the US war on Iraq, may be tapped by Chirac to counter Sarkozy, perhaps by becoming prime minister.

France's opposition Socialist party, meanwhile, is riven by a bitter argument over whether to recommend ratification of the EU's new constitutional treaty, which Chirac has promised will be put to the public in a referendum next year.

Party secretary Francois Hollande, who favours the constitution, has organised a party vote next Wednesday but there is a real possibility he will be opposed by the majority of members.

Supporters of the EU constitution fear that a no vote in the Socialist camp would encourage opposition nationally, leading to the treaty's rejection in next year's referendum. Under EU rules the constitution would then be technically defunct.