The mother of imprisoned WikiLeaks founder Julian Assange has appealed for his immediate release from Belmarsh Prison over fears he could catch coronavirus while behind bars.

Christine Assange's plea came after a leading prison boss warned last week that the worsening Covid-19 epidemic will kill inmates throughout the UK, describing the conditions inside jails as a fertile breeding ground for the virus.

Coronavirus cases have surged throughout the UK in recent days, with 14 more deaths confirmed on Sunday. More than 1,500 people nationwide have tested positive for the virus since the outbreak began, but officials say the true figure of people with the disease is likely to be far higher.

In a series of posts on social media, Ms Assange described her son as being "weak from chronic illness" and implored Britons and Americans to push politicians into action over his case. Those with underlying health conditions are more at risk of contracting the virus.

"Bail him now to save his life from #COVID19," she wrote.

Assange, 48, has been held in Belmarsh since last September over his alleged leaking of classified US military documents, including secret cables concerning conflicts in Afghanistan and Iraq.

He previously spent several years inside the Ecuadorian embassy in London, where he was granted political asylum, before eventually being evicted in April 2019 and arrested by The Metropolitan Police.

The Australian national now faces possible extradition to the US to face trial over the 18 charges levelled against him by Washington, with a long-awaited hearing over his case beginning last month in London's Woolwich Crown Court.

US prosecutors accuse Assange of working with military analyst Chelsea Manning to hack computer systems and leak vast amounts of classified State Department and Pentagon documents.

Assange is fighting the extradition request, with his lawyers arguing the charges amount to a politically motivated abuse of power.

He claims the case against him has been tainted by alleged spying while he was living in the Ecuadorian embassy, and argues he should not face charges as the WikiLeaks disclosures were part of a legitimate journalistic enterprise.

However the US government insists he is responsible for “one of the largest compromises of classified information in the history of the United States”.

The court battle over his possible extradition is scheduled to conclude later this year, in May.