21 February 2015
Last updated at 10:05
Stewart plays the personal assistant to a star actress in her award-winning role
Kristen Stewart has become the first US actress to win a Cesar award, the French equivalent of the Oscars.
She got a best supporting actress gong for her role in film drama Clouds of Sils Maria.
The big winner of the night was Timbuktu, which won seven awards including best film and director.
It depicts life in northern Mali under the control of Islamist militants, and is competing for best foreign film at Sunday’s Oscars.
Accepting the prize, Stewart shouted “I love you Juliette” in French to her co-star Juliette Binoche.
She later paid tribute to French filmmakers.
“The reasons why people make films here in France are very different from the reasons why people make movies in Hollywood and I prefer it here a little bit,” she told Variety.
There also was recognition for another American actor, Sean Penn, who got a lifetime achievement award.
In his acceptance speech, Timbuktu director Abderrahmane Sissako called France a “magnificent country” for its response to the deadly Islamist attacks last month.
“There is no clash of civilisations. There is a meeting of civilisations,” he said.