Don't expect her to open flower shows or host coffee mornings, do expect her to party until dawn and appear on the front cover of the world's glossy magazines.

The Italian-born Carla Bruni, who married President Nicolas Sarkozy on Saturday, looks certain to be an unconventional first lady and faces a testing time if she wants to win over the heart of a sceptical France.

A feline star of the catwalk turned celebrated chanteuse, Bruni brings undoubted glamour to the opulent Elysee Palace and marks a complete break with the wives of many previous presidents, who were often remote and discreet matrons.

But the supersonic speed, and non-stop media coverage, of their romance, has raised hackles even in liberal France.

Barely eight months after winning office, four months after a painful divorce and three months after first meeting Bruni, Sarkozy now has a third wife — and a second first lady.

He is 53, she is 40. He is a right winger with a reputation as a tough upholder of law and order, she is a Socialist voter who demonstrated last year against his immigration policy.

"I can't believe it is real. It must be a show. It has all gone too fast and I don't think she understands what she has let herself in for," said Christelle Wolf, a 32-year-old Parisian walking past the Louvre museum on Sunday morning.

"As first lady of France she will be locked up in the Elysee and she won't accept it. She is too libertine to be tied down."

Although Sarkozy is her first husband, Bruni has described herself as a "man tamer" and has had a number of affairs with intellectuals and rock stars, including Mick Jagger and Eric Clapton, and has a young son from a previous relationship.

Whodatedwho.com lists 11 boyfriends, French news magazines suggest the figure is nearer 40 and in an interview published last year, that she might now regret, Bruni was quoted as saying: "I get crazily bored by monogamy."

In some ways, Bruni is perfectly cast for her new role.

A patrician upbringing means she can move easily at the highest levels of society, she speaks at least three languages fluently and her modelling past ensures that she won't be afraid of the media circus that will now accompany her every move.

But her obvious indifference to bourgeois convention could get her into difficulty in the Elysee's rarefied air.

"Oh the tedium that takes hold of me when I do things for the sake of social correctness or out of professional obligation," she once told Marie Claire magazine.

Sarkozy's last wife, Cecilia, also once went on the record as saying she was not politically correct and she survived little more than four months in the Elysee. Burnt by the Cecilia experience, Sarkozy will no doubt be mindful that his new wife should not be caged in and Bruni's mother, Marisa Borini, has said that her daughter will continue her career as a musician despite her new role.

"Both Sarkozy and Carla Bruni are going to have to improvise and create a role for her that did not exist in previous presidential protocol," said Jean Luc Parodi, director of research at the National Foundation of Political Science.

Sarkozy's ratings slumped after his new romance was splashed across the press at the end of 2007, with voters accusing the president of being overly impetuous and caring more about his private life than the country's mounting economic problems.

Perhaps in response to these attacks, Saturday's wedding was about as low key as possible and Parodi did not expect the marriage would have a further negative impact on the polls.

"In fact the wedding might stabilise things because it regularises a relationship that didn't really conform with what the French expected from a president," he added.

Sarkozy's association with the internationally famous Bruni helped earn him the nickname President Bling Bling, a slang term associated with high living and big spending.

Certainly Bruni comes with independent wealth thanks to her artistic career and industrialist family, and one newspaper reported that she had offered to buy Sarkozy a jet.

But French voters would never sanction such ostentation and will demand a certain level of decorum. "As president, Sarkozy should set a good example. By marrying so soon after his divorce he has got off to a bad start and is going to have to be careful now on," said Christophe Dunglas, 47, as he walked his dog through central Paris. ¿ Reuters