Joran van der Sloot's U.S. Extradition Approved

The Peruvian Supreme Court has approved the extradition of Joran van der Sloot to the U.S. on charges of extorting money from the family of missing Alabama teen Natalee Holloway.

There is just one small catch -- Van der Sloot's extradition will not take place until he serves out his 28-year sentence for the 2010 murder of 21-year-old Stephany Flores. The Peruvian business student was killed five years to the day after the unsolved disappearance in Aruba of Holloway.

"We were surprised by how quickly the extradition request was heard," Van der Sloot's attorney, Max Altez, told Reuters. "We think there is a lot of pressure from the U.S. government."

PHOTOS: JORAN VAN DER SLOOT (Article Continues Below)

Natalee Holloway

Friday's ruling is not bad news for the prosecution, according to an international defense expert.

"There is an upside because the U.S. now has several years to put together a murder investigation. On murder, there is no statute of limitations," said Michael Griffith, senior partner at the International Legal Defense Counsel.

Van der Sloot has been indicted in the U.S. on charges that he extorted $25,000 from the mother of Natalee Holloway. The 18-year-old from Mountain Brook, Ala., vanished while on a class trip to Aruba. She was last seen leaving an Oranjestad nightclub with van der Sloot, then a 17-year-old Dutch honors student living in Aruba. Holloway's body has never been found, and van der Sloot has not been charged in her disappearance.

Prosecutors said that in exchange for the money he received from Holloway’s mother, van der Sloot promised to reveal how Holloway died and the location of her body.

Van der Sloot, 24, is serving a 28-year prison sentence at Piedras Gordas prison in Ancon for the murder of Flores. The Peruvian business student was found stabbed to death in van der Sloot's Lima hotel room on June 2, 2010.

Van der Sloot will be eligible for parole after serving one-third of his sentence. He could be extradited in as few as seven years.

According to Griffith, whose most renowned case, involving an American incarcerated in a Turkish prison, was the basis for the film and book "Midnight Express," Van der Sloot would likely face a five- to 10-year sentence in the U.S. for the alleged extortion. But, it is possible additional charges related to Holloway could be filed later.

"Maybe by the time he is released, [the U.S.] will have an airtight case against him in Natalee Holloway's disappearance," said Griffith.