A million dollars' worth of jewellery to be worn by celebrities at the Cannes film festival has been stolen, according to French police.

The items, which were snatched from the room of a Chopard employee at the Hotel Novotel, were in a security box, which was smashed and taken away.

The creations by the Swiss luxury jeweller had been scheduled to be worn on the red carpet, which has become as much a showcase for haute couture designers and extravagantly priced jewellery, particularly diamonds, as it is for films.

Chopard has long featured among the designer names worn by stars at events such as the Oscars. It has been a sponsor of Cannes for 16 years, competing to complete celebrities' outfits with a 40-strong team working around the clock at the festival.

Caroline Scheufele, co-vice-president of Chopard, told the Evening Standard this week that the firm prepares for the festival by taking requests from actors and their stylists.

"The Americans are so organised. They know what dress they're wearing months before and they tell us how their hair will be," she said. "The Europeans are much cooler about the whole thing. They don't have an entourage around them. Things can change at the last minute."

Since 1998, Chopard has also designed the Palme d'Or award, presented for best film.

So far, the actor Julianne Moore and models Cindy Crawford and Cara Delevingne have worn Chopard pieces at the festival this week.

In an ironic twist, the jewels went missing between around 8pm and 3am on Thursday night, just as Sofia Coppola's The Bling Ring had its premiere.

The film is based on the true story of a group of suburban Los Angeles teenagers, some from privileged backgrounds, who stole luxury goods from the houses of the rich and famous out of a desire to possess their wardrobes and lifestyles.