WikiLeaks founder Julian Assange is set to begin his latest legal battle later when he fights extradition to Sweden.

The 39-year-old Australian computer expert, who has infuriated Washington by releasing details of secret US diplomatic cables on his website, is wanted for questioning by Swedish prosecutor Marianne Ny over allegations of sexual offences made by two female WikiLeaks volunteers.

In December British prosecutors acting on behalf of Sweden failed in their High Court bid to deny Assange bail and he was released from solitary confinement in Wandsworth prison.

Assange has been staying under virtual house arrest at the Suffolk mansion of his friend, the founder of the Frontline Club Vaughan Smith, as part of his strict bail conditions.

At Belmarsh magistrates court, Assange's lawyers will argue that if Assange is sent to Sweden, he will run the risk of then being extradited to the United States, facing the death penalty or be held in Guantanamo Bay.