LONDON (AFP) - WikiLeaks founder Julian Assange can be extradited to Sweden to face rape and sexual assault claims, a British judge ruled Thursday after throwing out arguments that he would face an unfair trial.

   Lawyers for Assange immediately said they would appeal, setting up a legal battle through Britain's appeal courts that could postpone the 39-year-old Australian's ultimate fate for months.

   "I must order that Mr Assange be extradited to Sweden," judge Howard Riddle said in a decision at Belmarsh Magistrates Court in southeast London, following a three-day extradition hearing earlier this month.

   Assange, wearing a dark suit and tie, sat stony-faced in the dock at the top security court as the decision was read out.

   Celebrity backers including socialite Jemima Khan and rights campaigner Bianca Jagger also attended the hearing along with around 100 journalists from around the world.

   "We will be appealing," Assange's lawyer Geoffrey Robertson told the court after the verdict.

   Former computer hacker Assange says the claims against him, made by two women he met during a seminar organised by the whistleblowing website in August last year, are politically motivated because of the work of WikiLeaks.

   Assange rocked the world's diplomatic institutions and infuriated Washington last year when WikiLeaks began releasing more than 250,000 secret diplomatic cables sent by US embassy staff.

   It has also published sensitive data on the wars in Iraq and Afghanistan.

   Judge Riddle threw out arguments by Assange's legal team that the Swedish prosecutor had no power to issue a European arrest warrant and that the allegations did not amount to extradition offences.

   "In this country that would amount to rape," Riddle said about the allegation by one woman that Assange had unprotected sex with her while she was asleep.

   He said that Assange's Swedish lawyer Bjorn Hurtig made a "deliberate attempt to mislead the court" when he said that he had been unable to contact Assange to arrange an interview with Swedish prosecutors.

   Riddle also dismissed arguments that Assange could not face a fair trial as some evidence would be held behind closed doors, and that it was possible he would be re-extradited to the United States where he could face the death penalty.

   Riddle said that the arrest warrant was valid and said he had to uphold the "mutual respect and confidence this court has in our European counterparts."

   The judge also said it was "highly unlikely" that comments by Swedish Prime Minister Fredrik Reinfeldt that Assange lacked respect for women's rights would have an effect on the case.

   Karin Rosander, a spokeswoman for the Swedish prosecutor, said only that they would "see if they appeal or not" before issuing a "very short statement"

later.

   Assange was arrested in Britain on December 7 on an international warrant issued by a Swedish prosecutor who wanted to question him over four separate allegations of sexual assault made by the two women.

   He spent nine days in prison until he was released on bail in December and has since been staying at a friend's country mansion in eastern England under strict conditions including that he obey a curfew, wear an electronic ankle tag and report to police daily.

   The judge relaxed his conditions for Thursday's hearing to allow him to spend the previous night at the Frontline media club in London.

   Assange claimed his greatest fear was eventual extradition to the United States, where his lawyers argued he could be sent to the Guantanamo Bay detention facility or face the death penalty.

   He recently said his site was "significantly influential" in the fall of Tunisian leader Zine El Abidine Ben Ali, an event he said "no doubt" sparked uprisings across the Middle East.