Film director Roman Polanski is determined to fight his detention in Switzerland and extradition to the United States.
Lawyer Herve Temime said he is "in fighting mood" and his legal team would seek his release "without delay".
Polanski, 76, is wanted in the US for sentencing for having unlawful sex with a girl, then aged 13, in 1977. He pleaded guilty at the time but then fled abroad.
The BBC reports Polanski is still in custody in a Zurich prison. He was detained on Saturday when he arrived to receive a lifetime achievement award at the Zurich Film Festival.
His work includes films The Pianist, Chinatown, Tess and Rosemary's Baby.
French culture minister Frederic Mitterrand said President Sarkozy was following the case "with great attention".
Polanski has been visited in prison by French and Polish diplomats.
The BBC reports he was initially indicted on six counts and faced up to life in prison. Polanski has not been in the United States for more than 30 years.
The woman at the centre of the case, Samantha Geimer, has previously asked for the charges to be dropped. She has already sued Mr Polanski and reached an undisclosed settlement.