WikiLeaks founder Julian Assange has said he will turn himself over to UK police on Friday, Feb 5, if a UN panel rules he has not been unlawfully detained, BBC News reports.

In a statement on Twitter, Assange said he would accept there was "no meaningful prospect of further appeal".

He has not left the Ecuadorian Embassy in Knightsbridge, west London, since June 2012 after being granted asylum.

Assange has been fighting extradition to Sweden over a claim of sexual assault, which he denies.