Julian Assange is taking his appeal to Sweden’s highest court in a final attempt to lift a 2010 arrest warrant against him.
Lawyers for WikiLeaks founder Julian Assange have filed an appeal to Sweden's Supreme Court seeking to quash the 2010 warrant for his arrest on accusations of rape and molestation.
Assange's lawyer Per Samuelsson said he lodged the appeal with Sweden's top court on Wednesday afternoon to end the stand-off.
The Australian remains holed up in Ecuador's embassy in London to avoid arrest and extradition, while Swedish prosecutors refuse requests he be questioned there.
"We have to end this - the situation is completely stalled, and that's the point we raised in our appeal," Samuelsson said in criticising what he called the "total passivity" of prosecutors who he said "have done nothing in four years".
With the law requiring judges to decide if they are legally competent to accept the appeal, Samuelsson said "the Supreme Court now has the ball".
The arrest warrant was issued in 2010 by Swedish prosecutors investigating a case based on one woman accusing Assange of rape and another alleging sexual molestation.
Assange, 43, refused to return to Sweden to refute the charges he adamantly denies on fears Stockholm would extradite him to the US to be tried for his role in WikiLeaks' publication of huge stores of classified diplomatic, military and intelligence documents.
In 2012, he sought refuge in Ecuador's British embassy to avoid arrest and likely forced extradition to Sweden.
He has proposed to testify in the Swedish inquiry from inside that mission, but prosecutors insist Assange must return to Stockholm to be interviewed.
Little has evolved since then and after a lower Swedish court rejected the warrant appeal in November, Assange's lawyer took the motion to the Supreme Court.
"The prosecutor has literally not done anything since the autumn of 2010. This violates not only Swedish law, but also European law," Samuelsson told the online edition of Stockholm daily Dagens Nyheter.
Samuelsson said Assange wanted to clear his name and end the impasse.
"We are asking the court to give us access to the phone text messages that the two plaintiffs exchanged, and which (prosecutors) possess," he said, adding he was certain contents of the messages would prove Assange's innocence.
The Supreme Court only considers cases where it is important to establish a judgment - or precedent - that may provide guidance for lower courts.
Samuelsson says Assange's embassy exile costs 11,000 euros ($A15,830) each day. Moreover, he argues that in making it impossible for Assange to leave the mission without near certain arrest, the Swedish warrant has effectively denied Assange his civic rights before he's even been tried.