The request has been forwarded to Zurich authorities, who will hold a hearing on an unspecified date to decide whether Polanski should be sent back to Los Angeles. If extradition is approved, Polanski may appeal the decision to Switzerland's top criminal court and, theoretically, to the Federal Supreme Court.
That means the director of such film classics as "Rosemary's Baby" and "Chinatown" could remain in a Swiss jail for months more of legal wrangling, even though legal experts say he has little chance of avoiding a return to the United States after 31 years as a fugitive.
The maximum sentence Polanski can receive in California is two years, the Justice Ministry said.
"In the American case, he declared himself guilty of having sexual relations with a minor," spokesman Folco Galli told Europe-1 radio. "According to American law currently in force, the maximum penalty for the crime in question is two years in prison."
Galli later told The Associated Press that the sentence couldn't be longer because Polanski could only be punished for the crime that is the basis of his extradition. He said the U.S. informed the Swiss of the maximum sentence in its filing.
In Paris, Polanski's lawyer said the director would fight extradition.
"He will oppose this request and continue to ask to be released until the request is examined," Herve Temime said.
The U.S. had until late November to file for extradition, but the Swiss were already asking on Oct. 5 that the Americans expedite the process, according to documents obtained by the AP.
In an e-mail exchange obtained by the AP under U.S. public records request, Los Angeles prosecutors noted that the "Swiss were very eager to receive an advance English copy of our papers" and "the sooner that the Swiss knew we had filed formal papers the better."
There was no mention in correspondence of the intense public scrutiny over Polanski's arrest in the Alpine country, which tipped off U.S. authorities that he was expected five days before his apprehension at Zurich's airport.
Swiss officials have defended the move as routine procedure. But several politicians and commentators have argued that Switzerland may have cooperated too energetically, and that recent U.S.-Swiss troubles over wealthy American tax cheats and Swiss banks may have provided motivation for the arrest.
Polanski, who won a 2003 directing Oscar in absentia for "The Pianist," was accused of raping the 13-year-old girl after plying her with champagne and a Quaalude pill during a modeling shoot in 1977. He was initially indicted on six felony counts, including rape by use of drugs, child molesting and sodomy.
Polanski pleaded guilty to the lesser charge of unlawful sexual intercourse. In exchange, the judge agreed to drop the remaining charges and sentence him to prison for a 90-day psychiatric evaluation. Polanski was released after 42 days by an evaluator but the judge said he was going to send him back to serve the remainder of the 90 days. Polanski then fled the country on Feb. 1, 1978, the day he was to be sentenced.
A French native who moved to Poland as a child, Polanski has lived in France since fleeing the United States. France does not extradite its citizens.
Polanski has been fighting since his arrest to be released from jail. He suffered a serious setback earlier this week when the Swiss Criminal Court rejected his appeal because of the high risk he would flee justice again. It turned down a bail payment of his Alpine chalet in Gstaad, house arrest and electronic monitoring as conditions for his release.
The loss appeared to prompt some rethinking of his defense, when one of Polanski's lawyers said Wednesday that it was possible that the director might voluntarily return to face justice in the United States.
But that suggestion was quickly rejected by another attorney representing Polanski.