Julian Assange, the Wikileaks founder says he is willing to get arrested by the British Police on Friday, provided the UN investigation team does not rule that he is being illegally. Assange has been staying in the Ecuadorian Embassy in London since the last three and half years, after Sweden sought his extradition in relation to sexual assault allegations made against him by two women.

In a statement issued by WikiLeaks on Twitter, Assange said: “Should the UN announce tomorrow that I have lost my case against the United Kingdom and Sweden, I shall exit the embassy at noon on Friday to accept arrest by British police as there is no meaningful prospect of further appeal.

“However, should I prevail and the state parties be found to have acted unlawfully, I expect the immediate return of my passport and the termination of further attempts to arrest me.”

Apprehensions over his further extradition to the United States had made him raise repeated concerns about Swedish demands that he be questioned in person over the allegations. A grand jury investigation is still believed to be underway in the US following WikiLeaks’ publication of the Afghan war diary and United States diplomatic cables.

The United Nations working group on arbitrary detention is set to hand down a determination on Assange’s case on Friday morning. The decision is considered to be Assange’s last legal attempt for a ruling that his detention is arbitrary and unlawful. It rests on a challenge to the European extradition system, his inability to access the benefit of the grant of asylum by Ecuador, and what he argues is his long-term detention.

The whistleblower first entered the Ecuadorian embassy in 2012 after mounting a series of legal challenges in the UK to an extradition warrant from Sweden.