WikiLeaks founder Julian Assange is yet to be shown key evidence in the case brought against him by the American authorities, his extradition hearing was told today.

The 48-year-old, faces accusations of leaking sensitive United States' military material between January and May 2010.

The Australian national appeared at Westminster Magistrates' Court over video-link from HMP Belmarsh white haired and clean shaven with a grey jumper and spoke to confirm his identity.

The Americans want to extradite him to US soil so he can be prosecuted for conspiring with army intelligence analyst Chelsea Manning for leaking classified documents.

WikiLeaks founder Julian Assange gestures from the window of a prison van as he is driven into Southwark Crown Court in London on May 1, 2019. He appeared via video linking today at Westminster Magistrates

Assange is currently being held at Belmarsh prison (pictured above) which has housed some of the UK's most notorious prisoners

He is being held in the high-security jail ahead of a full hearing in February when he will fight extradition to the US, where he faces 18 charges, including conspiring to hack into a Pentagon computer.

Gareth Peirce, representing Assange, said: 'The summary case which we have prepared is a dense document.

'Mr Assange has not been given what he must be given, and we are keen to go through this to the best of our abilities to keep with the requests of the court.

'It is predicated on the underlying evidence that Mr Assange has not reviewed.'

Last month Swedish authorities dropped rape allegations made in 2010 against the editor.

Asaange appeared at Westminster Magistrates' Court (pictured above) over video-link. His supporters had previously demonstrated outside court

Julian Assange pictured as he is led out of the Ecuadorian Embassy in London in handcuffs following his sensational arrest by British police earlier this year

Assange had taken refuge in a small office, converted into a bedroom in Ecuador's embassy since 2012 before he was finally evicted earlier this year.

He was then jailed for 50 weeks for breaching bail on 1 May.

District Judge Vanessa Baraitser told Assange: 'I am now adjourning your case to next Friday, 19 December, when a case management hearing will take place.

'You will be produced as was request by both sides over the video link.'

It comes weeks after more than 60 doctors warned in an open letter addressed to Home Secretary Priti Patel that he could die in prison without urgent medical care.

The medics, from the UK, Australia, Europe and Sri Lanka, expressed 'serious concerns' about Assange's fitness to stand trial.

He was jailed for 50 weeks in May for breaching his bail conditions after going into hiding in the Ecuadorian embassy in London to avoid extradition to Sweden over sex offence allegations, which he has always denied.

Last month, WikiLeaks welcomed a decision by the Swedish authorities to drop a rape investigation.

Assange has been in custody since he was dramatically removed from the embassy building in April, and at a hearing in October appeared to struggle to say his own name, telling Westminster Magistrates' Court: 'I can't think properly.'

Last month, Assange's close friend Pamela Anderson claimed she was threatened by a prison warden at Belmarsh.

Anderson said that towards the end of her meeting with Assange at Belmarsh high security prison in London in May the warden 'stormed in and made it very clear to me, that if I were going to be a problem - he'd make problems for Julian. It was a direct threat'

The snap taken before Assange was thrown in prison shows the close relationship the pair share amid rumors there are romantically linked

Anderson said that towards the end of her meeting with Assange at Belmarsh high security prison in London in May the warden 'stormed in'.

She said: 'The warden stormed in and made it very clear to me, that if I were going to be a problem - he'd make problems for Julian. It was a direct threat.'

It was unclear why the warden, who is known as the prison governor in the UK, might have believed Anderson was going to cause trouble.

A UK Prison Service spokesman said: 'The Governor of HMP Belmarsh did not threaten Ms Anderson or Mr Assange.'

On November 25, Home Secretary Priti Patel received a letter from medics across the world which stated Assange 'could die' at Belmarsh if he didn't receive 'urgent medical care'.

The medics - from the UK, Australia, Europe and Sri Lanka - express 'serious concerns' about the 48-year-old's health.

The letter to Priti Patel, pictured, which was also copied to shadow home secretary Diane Abbott, says: 'From a medical point of view, on the evidence currently available, we have serious concerns about Mr Assange's fitness to stand trial in February 2020'

The doctors are calling for Assange to be transferred to a university teaching hospital, where he can be assessed and treated by an expert medical team.

The letter, which has also been copied to shadow home secretary Diane Abbott, says: 'From a medical point of view, on the evidence currently available, we have serious concerns about Mr Assange's fitness to stand trial in February 2020.

'Most importantly, it is our opinion that Mr Assange requires urgent expert medical assessment of both his physical and psychological state of health.

'Any medical treatment indicated should be administered in a properly equipped and expertly staffed university teaching hospital (tertiary care).

'Were such urgent assessment and treatment not to take place, we have real concerns, on the evidence currently available, that Mr Assange could die in prison.

'The medical situation is thereby urgent. There is no time to lose.'

Dr Lissa Johnson, a clinical psychologist in Australia and one of the letter's signatories, said: 'Given the rapid decline of his health in Belmarsh prison, Julian Assange must immediately be transferred to a university teaching hospital for appropriate and specialised medical care.

'If the UK Government fails to heed doctors' advice by urgently arranging such a transfer on medical grounds, there is a very real possibility that Mr Assange may die.

'As it stands, serious questions surround not only the health impacts of Mr Assange's detention conditions, but his medical fitness to stand trial and prepare his defence.

'Independent specialist medical assessment is therefore needed to determine whether Julian Assange is medically fit for any of his pending legal proceedings.

'Consistent with its commitment to human rights and rule of law, the UK Government must heed the urgent warning of medical professionals from around the world, and transfer Julian Assange to an appropriately specialised and expert hospital setting, before it's too late.'