When organizers of the Cannes Film Festival announced weeks ago that it would open with Woody Allen's "Midnight in Paris," which features French first lady Carla Bruni-Sarkozy in a small but much-hyped role, the paparazzi had visions of the one-time top model and President Nicolas Sarkozy racheting up the bling factor on the red carpet.

But the Sarkozys were sitting out the premiere Wednesday evening, much to the chagrin of hundreds of photographers and cameramen who cover the 12-day-long French Riviera cinema extravaganza.

The no-show has fueled speculation that Bruni-Sarkozy is pregnant.

Asked head-on in an RTL radio interview Tuesday about whether she was expecting a child, Bruni-Sarkozy said: "It's a private question." She also said regretted she would not be in Cannes "for personal and also for professional reasons."

She didn't enumerate those reasons, and the omission has fanned recent French media speculation that she may be pregnant. The rumors surfaced in late April, when gossip magazine Closer ran a story saying the 43-year-old first lady was three months pregnant. The magazine said that officials were keeping it under wraps because her age makes it a high-risk pregnancy.

When asked about the rumors, Bruni-Sarkozy has consistently demurred, though she's never come out and said they were false — which some here have interpreted as affirmation. French media have also pointed to the willowy former model's new habit of covering her belly with a strategically placed pashmina during recent official appearances as evidence that she's expecting.

A pregnancy could be a potential strategic coup for Sarkozy. With the presidential election coming up in less than a year and recent polling showing the conservative leader's numbers plummeting, a baby in the Elysee presidential palace could be a way back into voters' hearts, some observers remark.

At a news conference Wednesday, Allen gave the speculation a wide berth, saying only that it had been a pleasure to work with Bruni-Sarkozy, who plays a Parisian tour guide and appears in all of three scenes.

Allen explained that he was dining with the French leader "and she (Bruni-Sarkozy) walked into the room and I thought she was very beautiful and very charming and charismatic.

"I just said 'would you like to be in a movie, just in a small role, just for fun? I know that you are very busy,'" Allen recalled. "She said: 'I would like to be in one of your movies because I'd like to tell my grandchildren one day that I was in the movie.'

"She was everything that I thought she would be," he said. "She came in and did her part very gracefully and ... she played the character perfectly."

From a wealthy family from the Italian city of Turin, Bruni-Sarkozy had a successful career as a model before becoming a singer-songwriter, known for her soulful lyrics and wispy voice. She's also known for her topsy-turvy romantic life, which included relationships with the likes of Mick Jagger and Eric Clapton.

She met Sarkozy in late 2007, and the two married in a small ceremony in the Elysee a few months later.

Sarkozy has three sons from his two previous marriages. She has one son from an earlier relationship.