US school children warm to chic Carla Bruni

Carla Bruni-Sarkozy turned up the heat on her first trip to Washington as France's first lady, visiting a school in a poor neighbourhood and lunching at Ben's Chili Bowl.

The ex-top model later met US first lady Michelle Obama for dinner with their husbands - behind firmly closed doors in the Obamas' private residence quarters in the White House, leaving the curious guessing about how the glamorous four got along and whether their children joined them.

The White House put such a clamp on the dinner details that not even the menu was released.

Youngsters at Washington's KIPP DC charter school were over the moon at their visitor and her entourage of bodyguards and serenaded her with Ain't No Mountain High Enough.

Mrs Bruni-Sarkozy read them a book from the Madeline series about a girl living in France - in English, which the Italian-born French first lady speaks fluently. When eighth-graders asked her about her favourite museum she responded, to their delight: "If you come to Paris I'll bring you to the Louvre and I'll show you the Mona Lisa, and then we'll go to the restaurant."

Mrs Bruni-Sarkozy, who took up a singing career after quitting the catwalk and is now active in foundations fighting illiteracy and Aids, had surprised pupils at Juilliard Music School with a visit the day before in New York.

Yesterday, after the motorcade bell rang and her school visit ended, she joined her husband, French president Nicolas Sarkozy, and his 12-year-old son Louis for lunch at Ben's Chili Bowl, a diner that has been a long-time fixture in Washington's black community and is a frequent stop for politicians and celebrities.

Barack Obama ate his first meal at the local landmark several days before his inauguration last year.

Mr Obama, standing alongside Mr Sarkozy at a White House appearance later, noted that the French were famous for their cuisine and remarked with a smile that the lunch choice - apparently a "half smoke" sausage - "shows his discriminating palate".

The Sarkozys' trip took on an air of a family holiday. Louis came to meetings on Capitol Hill with Senator John Kerry and House of Representatives speaker Nancy Pelosi, and Mr Sarkozy's gift to the Obama family was some Asterix comic books for daughters Sasha and Malia.

The Sarkozys' visit to New York at times seemed a loveathon, as they were photographed kissing in front of their hotel and in the Boathouse restaurant in Central Park, and clasping hands before and after the French president gave his speech at Columbia University.

The French first lady, though, remains an enigma for her many admirers, as well as her detractors.

She charmed the Queen but has spurned fellow first ladies during other international visits. She travels irregularly with her husband, and is reported to live in her Paris apartment part of the time instead of in the presidential palace.

But she and Michelle Obama appear to have established a rapport in their few meetings - often judged more as fashion face-offs by two fit, well-dressed and confident modern women than anything else.

Mrs Bruni-Sarkozy, in her three days in the US, has been photographed wearing at least six different outfits, from a wraparound black top and grey skirt at Columbia University, to wide-leg taupe trousers at the school yesterday.

Her hairstyles kept up, with a swept-up chignon at Columbia giving way to loose tresses at Juilliard.