A Swedish appeal court has upheld an arrest warrant against Wikileaks founder Julian Assange, wanted for questioning over sexual assault claims.
The Court of Appeal refused Mr Assange's attempt to have a detention order issued in 2010 revoked.
Mr Assange, who denies the allegations, has sought refuge in the Ecuadorean embassy in London to avoid extradition.
If he goes to Sweden, he fears he could be extradited to the US to face charges of leaking government documents.
Wikileaks has published thousands of secret documents, which have caused intense embarrassment for the US and lifted the lid on diplomatic relations.
Two women in Sweden accuse Mr Assange, 43, of sexual assault.
Thursday's decision at the Svea Court of Appeal in Stockholm ruled on an appeal against a similar decision by a lower court.
Mr Assange's lawyers argued that the arrest warrant should be repealed because it could not be enforced while he was in the Ecuadorean embassy.
Analysis by BBC World Affairs correspondent Paul Adams
Before and during his self-imposed incarceration inside the Ecuadorean embassy, Julian Assange has been trying to clear his name through a whole series of legal hurdles. So far without success.
Mr Assange's lawyers have attempted to challenge the legal basis for the allegations against him. But the allegations won't go away and today's ruling, while critical of the prosecution's failure to move the investigation forward, makes it plain that Mr Assange still has a case to answer.
It offers no opinion on Mr Assange's claim that he cannot leave the safety of the Ecuadorean embassy without running the risk of being extradited to the United States and jailed for his role in the release of classified American military and diplomatic documents.
But the fact remains that no such US extradition request exists. A lengthy grand jury investigation has not apparently resulted in any form of indictment. In 2013, when former NSA contractor Edward Snowden began leaking his own stash of damaging material, the importance of Julian Assange suddenly receded.
The lawyers noted that Swedish prosecutors had not travelled to London to interrogate Mr Assange.
In a statement, the court said there was "no reason to set aside the detention solely because Julian Assange is in an embassy and the detention order cannot be enforced at present for that reason".
But it also criticised Swedish prosecutors for not making enough effort to explore "alternative avenues" to interrogate Mr Assange, saying the "failure of the prosecutors to examine alternative avenues is not in line with their obligation".
Per Samuelson, one of Mr Assange's lawyers, told Reuters news agency that he believed the court's comments were a "warning" to prosecutors, and that the warrant would be revoked at a future hearing.
He said the defence team would take the ruling to the Supreme Court.
Meanwhile, prosecutor Marianne Ny said in a statement: "Like the court of appeals says, there is every reason to continue considering how the case should be taken forward."
Mr Assange has not been formally charged in Sweden, but prosecutors want to question him over allegations of sexual misconduct and rape involving two women he met during a visit to the Scandinavian country in 2010.
The Wikileaks founder denies the allegations and has said they are part of a smear campaign against him.
The Ecuadorean government granted asylum to Mr Assange in 2012 after the UK Supreme Court refused to reopen his appeal against extradition.
Ecuador says there are fears his human rights might be violated if he is extradited.
Chelsea Manning, an American soldier formerly known as Bradley Manning, was sentenced to 35 years in prison in the US for passing documents to Wikileaks.
But no US extradition request for Mr Assange exists and a spokeswoman at the US embassy in London said Mr Assange was not currently a person of interest.
Timeline of allegations
- 20 August 2010: The Swedish Prosecutor's Office issues an arrest warrant for Julian Assange over allegations of rape and molestation, but withdraws the warrant a day later
- 1 September 2010: Swedish Director of Prosecution Marianne Ny says she is reopening the rape investigation against Mr Assange
- 30 May 2012: The UK Supreme Court rules that he should be extradited to Sweden to face questioning
- 16 August 2012: Ecuador grants asylum to Mr Assange, saying there are fears his human rights might be violated if he is extradited
- 16 July 2014: A district court in Stockholm court rules that the arrest warrant against Mr Assange will remain in place