Lawyers have made a formal request to a Swedish court to overturn Julian Assange's arrest warrant in a rape case.

The journalist has spent more than three years hiding in the Ecuadorian embassy in London after his appeal against extradition failed in the UK courts.

Thomas Olsson, one of Assange's lawyers, said in a statement: "We consider that there have arisen a number of new circumstances which mean there is reason to review the earlier decision".

Assange filed a complaint in 2014 with the UN committee - arguing that he was "arbitrarily detained" because he could not leave the embassy without being arrested.

He was first accused of one count of rape and another of molestation of two Swedish women by the Swedish Prosecutors' Office in August 2010 but was initially released and allowed to leave the country.

In pictures: Julian Assange's 'arbitrary detention' Show all 14 1 /14 In pictures: Julian Assange's 'arbitrary detention' In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Wikileaks founder Julian Assange speaks from the Ecuadorian Embassy on December 20, 2012 in London, England. Getty Images In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Supporters of Julian Assange show banners as they wait for his appearance opposite the Ecuadorian Embassy yesterday (Frank Augstein/AP) In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' A supporter of WikiLeaks founder Julian Assange demonstrates outside Ecuador's embassy in central London on February 5, 2016 In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Assange speaking to the media outside the Ecuador embassy in 2012 In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Fashion designer and political activist Vivienne Westwood to visit Wikileaks founder Julian Assange In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Members of the media wait outside the Ecuadorian embassy where Wikileaks founder Julian Assange continues to seek asylum in February 2016. In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Supporters of Assange wait for the arriveal of Ecuadorian Foreign minister Ricardo Patino (Andrew Cowie/AFP/Getty Images) In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' A supporter outside the embassy, which is guarded by police. The 24-hour operation is said to have cost the British taxpayer £3 million (Tal Cohen/EPA) In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Supporters of the WikiLeaks founder Julian Assange at a protest outside the Ecuadorean embassy yesterday, where he has been holed up for three years In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Supporters have appeared at the embassy numerous times over the last year, especially when Mr Assange is set to appear, as he did yesterday (Frank Augstein/AP) In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' The Foreign & Commonwealth Office have made clear that: “The UK has a legal obligation to extradite Mr Assange to Sweden” (Chris Helgren/Reuters) In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' Demonstrators hold banners outside the Ecuadorean Embassy in London, where Wikileaks founder Julian Assange is staying In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention' In pictures: Julian Assange's 'arbitrary detention' In pictures: Assange's 'arbitrary detention'

A few months later he was arrested for a second time in London and released on bail following an extradition hearing.

In 2012, the UK Supreme Court ruled that he should be extradited to Sweden to face questioning over the allegations - which he has said are "without basis".

After the ruling he entered the Ecuadorian embassy in Knightsbridge where he claimed political asylum - he alleges if he is sent to Sweden he will be rendered to the US to face trial and possible torture over his role in the Wikileaks revelations.

It comes as Sweden's Director of Public Prosecution, Marianne Ny, said they were working on a new request to interview Assange in London.

She said a previous request had been rejected by the Prosecutor-General of Ecuador in January.