WikiLeaks founder Julian Assange addresses a crowd outside the Ecuador embassy in west London last month.

London -

Left-leaning celebrities, academics and journalists once queued up to lend their support - and put their cash on the line - to back Julian Assange, who confronted the power of the United States by publishing secret diplomatic cables on his WikiLeaks website.

But Tuesday nine supporters, including a Nobel Prize-winning biologist, began their legal bid to save their money at Westminster magistrates' court. The court, meanwhile, urged his backers to try to persuade him to hand himself over to the authorities.

Supporters of the transparency campaigner face losing a total of £340 000 pledged to ensure he remained a free agent after allegations of sex offences in Sweden surfaced.

The sum was forfeited when he breached his bail conditions by holing up in the Ecuadorean embassy in London.

Other supporters, including Jemima Khan and the film director Ken Loach have already lost £200 000 after paying money into court to ensure Assange's bail.

The remaining backers, none of whom were present at the proceedings, are seeking to avoid paying sureties of £140 000 offered up on behalf of the 41-year-old, who was arrested in 2010 over allegations made by two women in Sweden.

Among those who offered sureties were the Marchioness of Worcester, Lady Caroline Evans, the wife of a former Labour minister, and the Cambridge scientist Sir John Sulston.

The others are the retired educationalist Professor Patricia David, author Phillip Knightley, Vaughan Smith, founder of the Frontline journalism club, Assange's girlfriend Sarah Harrison and his assistant Joseph Farrell.

Sarah Saunders, a Kent catering manager who offered a £20 000 surety, is believed to have already lost a substantial sum.

Under the terms of his bail conditions Assange was wearing an electronic tag and required to live and sleep at Saunders' home in Kent.

The Chief Magistrate Howard Riddle said his backers should urge Assange to give himself up, saying: “We trusted and put our faith in you - now come back.”

He added: “At the moment I am not persuaded that there any reason that securities would not be using every effort, publicly or privately, to persuade Assange to surrender himself to the UK authorities.

“I might change my mind but that's my position now.”

Assange breached his bail conditions when he sought political asylum in the embassy after losing his appeal against extradition to Sweden. Khan has already urged him to answer police questions in connection with the allegations, but Assange fears he would ultimately face extradition to the US from Sweden over his actions at WikiLeaks.

Henry Blaxland QC, representing four of his backers, said none could have predicted his actions nor could they reach him to persuade him to change his mind. “It was an extraordinary thing to do,” he said.

“Nobody could reasonably have foreseen that's what he would do. The anxiety was not that he would take the steps that he did, but that he might abscond in the conventional sense, or go into hiding.”

The hearing was adjourned until 3 October. - The Independent