The Sarkozy marriage they said wouldn’t last...

The evening has gone down in popular legend as the start of the "Nicolas and Carla Story", as the presidential romance is now known. It was, in the French language of love, a "coup de foudre" (lightning strike), or love at first sight.

"Nicolas was alone. His divorce had affected him. He said to me, 'Listen, invite me to a friends' dinner at your place with your pals. I don't want to spend evenings alone in the Elysée'," said Séguéla afterwards.

The President, somewhat rudely he later admitted, ignored all the other guests and spent the whole evening talking to Carla.

Séguéla recalled how Sarkozy had driven Carla home at around 2am. "Five minutes later she called me. She said, 'Your friend, he's a strange one. I gave him my telephone number and he hasn't called me'. He'd only left her five minutes before."

After a whirlwind romance the couple married a few months later at a private ceremony in the Elysée Palace. They will celebrate their second wedding anniversary next week and, according to friends, still behave like love-struck teenagers.

"Even with the passing of time it still has the same intensity. It's magical to see them together," says Séguéla this week.

"They treat each other with extraordinary tenderness and respect. They are very tactile. He has always been very tactile but it's like a permanent fusion with her. In private they are as one."

Sceptics who saw it as a marriage of convenience - he was desperately in need of a presidential wife, she was seeking an antidote to singledom ennui - have, for the moment at least, been proven wrong.

But they are still regarded as the odd couple. He is a 5ft 5in (one inch shorter than Napoleon), hyperactively ambitious career politician of the Right with a penchant for showy watches and stacked heels.

She is a 5ft 9in supermodel-turned-singer-songwriter now forced to wear flats, whose high-profile ex-boyfriends include Mick Jagger, Eric Clapton, Donald Trump and former socialist French prime minister Laurent Fabius, whose friends hail mostly from the political Left.

"They are a mix of water and fire but I have never seen them argue," says Séguéla. "It started with admiration and respect and then came the love and it is a love that will last.

"His political circle is to the Right and she has Left-wing friends but they are great together, very romantic. They are a mythical couple like Kennedy and Jackie O; like a couple in a love story."

He adds: "He calls her Carlita and she calls him 'mon amoureux' (my love) or 'mon mari' (my husband). Calling him 'mon mari' is important because although everyone knows she's had lovers before, she's never been married because, as she says, she'd never met the great love of her life. That's the difference between Nicolas and those who went before."

Unlike previous First Ladies, who disappeared behind the Elysée's voluminous curtains, reappearing in Chanel or Dior walking several paces behind their husbands at official events, Carla is not a political wife. She does not even live in the presidential palace.

Possibly mindful of her predecessor's description of it as a "house of mirrors where everything you do is known", she takes her son there only at weekends so he can play in the vast garden.

During the week Sarkozy leaves his gilded palace and drives, or is chauffeur-driven, to her house in the chic 16th arrondissement to spend cosy evenings en famille. Carla has said they prefer to stay in than go out on the town but when home is a £2 million mansion in the best part of town, who can blame them?

She also has her own career as a singer which, in a break with tradition, she is determined to continue. She spends much time playing her guitar and writing songs at home and is said to be working on two new albums, one in French and a second in English, to be released this autumn.

Although she vowed to give up performing publicly when she became First Lady, she took part in a New York concert to celebrate Nelson Mandela's 91st birthday last year.

She also sang a duet with Harry Connick Jr on French television and is to appear on a David Bowie tribute album later this year.

"I said to Nicolas, 'I cannot choose between you and my music, it's ridiculous. I'm not going to drop my job and iron my husband's shirts for the next four years'," she told British documentary-maker George Scott.

"So of course he didn't ask me to choose. I decided to keep my job. I'm glad he didn't ask me to choose. It would have been a wrench and a bad way of starting love. Love has nothing to do with sacrifice."

Séguéla admits it has been difficult for the First Lady to abandon the idea of giving concerts.

"She is a singer deprived of her stage and I know she suffers over this. But she accepts it because she loves her husband," he says.

However, Carla has agreed to star in Woody Allen's next film, due to be shot in Paris in the early summer. Admitting she said "yes" to the bespectacled American director without hesitation - much as she did to her husband's proposal - she adds: "I do everything a little bit blindly. If I don't, I won't do anything.

"When I'm a grandmother I'd like to be able to say I've done a Woody Allen film. If it ever comes about, it'll be a great experience."

Officially she is now a grandmother, or a step-grandmother, following the recent birth of a boy to the president's second son Jean, 23, and his wife, electrical chain heiress Jessica Sebaoun-Darty.

Named Solal - from the Hebrew "solel" meaning "to carve a path" - he was the reason for the Bonpoint shopping spree.

Carla also now has her own good cause, a World Foundation for Aids, set up in honour of her elder brother Virginio who died of an HIV-related illness in 2006.

While her husband has the permanently smug look of a cat that got the double cream whenever he is photographed with Carla on his arm, she is credited with being a calming influence on the man nicknamed "Speedy" Sarkozy.

She has also toned down his bling-bling tendencies, made him more cultured and even introduced the man who said he did not have time to read to literature.

"Our lives have changed, I have calmed him down. He likes to fill every moment, he is a man of action," she said in a recent interview.

"But our personal life is very soft, very calm, very tranquil. He has calmed me too in a certain way."

Though she has been accused of meddling in politics, she denies this vehemently. "I'm an artist. It's not my domain," she tells friends.

However, Georgina Oliver, a French fashion and style journalist, believes Carla has had a subtle improving effect on the President.

"She looks the part but she also whispers in his ear, telling him about important people in the world of arts and culture. She's a sort of cool Medici," she says.

"As a result, she may be quite a help to the Republic. He certainly commits fewer gaffes when she's around and while they used to talk about him as being one of the worst-dressed men in politics, and some still do, she has given him a total makeover."

Oliver adds that the Sarkozys appeared to be breaking with another French tradition.

"The French are used to the president's wife being a front and romance being found elsewhere, but Nicolas and Carla are cocking a snook at this," says Oliver.

"French people are associated with romanticism, and they are living icons of this, but it's hard to know how much they are miming and how much is true."

It is certainly true that Nicolas has promised to take Carla to the Taj Mahal for a belated honeymoon as part of an official trip to India.

They will not make it for Valentine's Day, as he had hoped, but the Elysée Palace says a visit is on the cards in the near future.

When they do eventually go, you can be sure we will not be seeing a repeat of the Prince and Princess of Wales' disastrous visit in 1992 when a forlorn Diana, fed up with her husband's infidelity, posed alone in front of the world's celebrated symbol of love. Quite the opposite, in fact.

"By nature I am solitary," Carla said recently. "But today I am better with him than without him. I would never have imagined that when I was young."