WikiLeaker-in-chief Julian Assange has lost his appeal against extradition to Sweden to face accusations of sexual harassment and rape, the UK Supreme Court ruled in the last hour.

Lord Phillips of Worth Matravers said that Assange's "request for extradition has been lawfully made and his appeal against extradition is lawfully dismissed".

He added that the five members to two of the Supreme Court panel concluded that the Swedish public prosecutor could be considered a judicial authority - thus enabling an extradition to take place.

After a two-day hearing in February, UK Supreme Court judges retired to consider their verdict in Assange’s latest shot at avoiding deportation to Sweden. They had focused on whether or not the Swedish prosecutor, who issued Assange's European arrest warrant, had the right to do so.

Clare Montgomery, the lawyer for the Swedish authorities, argued at the time that the Swedes were perfectly within their rights to demand Assange’s extradition, and warned that the European arrest warrant system could collapse if the WikiLeaker-in-chief walks.

That argument was a success at the Supreme Court today. The WikiLeaks founder was not in court to hear the judgment being handed down.

His QC Dinah Rose requested a stay of extradition and Phillips afforded her two weeks to consider the court's decision.

She may argue that the case should be "reopened" on the grounds that the Supreme Court members based the judgment on the Vienna Convention on the Law of Treaties – which, crucially, had not been discussed or argued during the proceedings.

It is possible Assange could take his case next to the European Court of Human Rights to halt or delay his transfer to Sweden.

Assange was ordered by a High Court judge to return to the Scandinavian nation to face rape and sexual molestation allegations brought against him by two women. The accusations surfaced after he visited the country in August 2010 to give a lecture.

Timeline to the extradition

The 40-year-old Australian was arrested by Scotland Yard in December 2010, and granted bail early last year after his lawyers secured about £200,000 from a number of celebrity friends.

In February 2011, Assange was told by Judge Howard Riddle at Belmarsh Magistrates Court, in south east London, that he would be extradited to Sweden.

In June that year he launched the High Court appeal hearing, but by November, the court upheld Judge Riddle's decision, declaring that it would not be unfair or unlawful to send Assange to face questioning in Sweden.

Assange – whose website has leaked 250,000 of confidential diplomatic cables – has been operating under strict bail conditions and has an electronic tag around his ankle.

The WikiLeaks man has denied any wrongdoing, and has said that his relations with both women were entirely consensual.

Swedish prosecutors have repeatedly requested that Assange make himself available for questioning. They issued a warrant for the WikiLeaker's arrest, but haven't filed charges in the case.

Assange has previously described the original UK court decision as "the result of a European arrest warrant system run amok". ®