Film director Roman Polanski is determined to fight his detention in Switzerland and extradition to the US, his lawyer has said.

Herve Temime (Polanski’s lawyer) said the Oscar winner was “in fighting mood” and his legal team would seek his release “without delay”.

US prosecutors want Mr Polanski to face sentencing for having unlawful sex with a 13-year-old girl in 1977. He pleaded guilty at the time but then fled abroad.

A petition has been signed by film-makers and actors including Monica Bellucci and Fanny Ardant expressing dismay at Mr Polanski’s arrest. Other Hollywood luminaries, including film producer Harvey Weinstein, have called for Mr Polanski’s release.

French culture minister Frederic Mitterrand said President Sarkozy was following the case “with great attention”. Mr Mitterrand also told France-Inter radio that he and the Polish Foreign Minister Radek Sikorski have written to US Secretary of State Hillary Clinton, and said there could be a decision as early as Monday if a Swiss court accepts bail. Mr Polanski has also been visited in prison by French and Polish diplomats.

French Consul General Jean-Luc Faure-Tournaire said the director “thanks the many people who have shown support”. Poland’s ambassador to Switzerland, Jaroslaw Starzyk, said Mr Polanski was “in good condition”.

The Swiss media has rounded on the authorities: “Switzerland let a guest walk into a nasty trap. We should be ashamed,” said tabloid newspaper Blick.

Mr Polanski was initially indicted on six counts and faced up to life in prison. He has not set foot in the US for more than 30 years.

The victim 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.