The Swiss authorities said they received the request on Thursday evening. Polanski's legal team said the director would lodge an appeal to fight being sent back.

The Franco-Polish filmmaker was arrested in Zurich on September 26 on the basis of a US warrant and taken into custody awaiting extradition.

The Academy Award-winning director was detained at Zurich airport en route to accept a lifetime achievement award from the Zurich Film Festival.

The US Embassy in Bern submitted the formal extradition request within the deadline established under a bilateral extradition treaty. The request is based on a warrant issued by the Superior Court of the State of California for the County of Los Angeles on February 1, 1978.

This was the date on which Polanski failed to appear before the judge as was required by his bail conditions.

During the US criminal investigation, Polanski had admitted to having unlawful sexual intercourse with a 13-year-old girl. He is wanted by the US authorities for sentencing for this offence.

The Swiss justice authorities said they would forward the extradition request to canton Zurich for the purpose of holding a hearing for Polanski. It will make its decision regarding extradition based on the results of the hearing and the information provided by Polanski's lawyer.

Justice Office authorities would not speculate on how long the process might take.

Right to appeal

In the event that extradition is considered to be admissible, Polanski will have the option of appealing against the Swiss government's decision before the federal courts – the criminal tribunal in Bellinzona and the supreme court in Lausanne.

After Polanski fled the US, the American extradition services became active after it was learned the director was living in France.

Officials in the US were kept abreast of the fugitive director's whereabouts over the years and repeatedly confirmed that the arrest warrant was still valid.

When Polanski was detained at Zurich airport last month, questions were raised why Switzerland decided to go after him at that time, even though the director was a frequent visitor to the country, where he owns a chalet in Gstaad.

A spokesman for the Swiss Justice Office, Folco Galli, defended the Swiss move in a statement to the Associated Press news agency earlier this week.

Swiss officials asked their American counterparts if their arrest warrant was still valid. After receiving confirmation, justice authorities said Switzerland was obliged by treaty to apprehend the director.

Galli also said that this was the first time officials had precise details on the director's arrival in Switzerland and an official American request to arrest him.

swissinfo.ch