Wikileaks founder Julian Assange has appealed to Britain's Supreme Court to block his extradition to Sweden over rape allegations.

Lawyers for the 40-year-old Assange told the court the European arrest warrant is invalid because it was issued by a Swedish prosecutor and not a judge or court.

Lawyers for Sweden are arguing that prosecutors play a judicial or semi-judicial role and therefore it is valid.

The Supreme Court hearing will last two days, and justices are expected to issue their decision within the coming weeks.

Assange has denied rape and sexual assault accusations against him. He says the allegations are politically motivated by governments angered at Wikileaks' activities.

In 2010, Assange's Wikileaks website published thousands of stolen, confidential U.S. diplomatic cables. They included sensitive information on anti-terrorism activities and candid views on foreign leaders.

Previous leaks included tens of thousands of confidential files on the wars in Afghanistan and Iraq.

Assange has claimed he risks being handed over to the United States for prosecution, if sent to Sweden.