Instead, following his expulsion and arrest last week, they protested outside the top-security Belmarsh prison in southeast London where he is being held, carrying placards demanding his release.

The WikiLeaks founder is in custody awaiting sentencing for breaching his British bail conditions in 2012 by seeking refuge in Ecuador's London embassy to avoid extradition to Sweden.

SEE ALSO: German MP visits Assange in embassy

He was arrested at the embassy on Thursday after Ecuador revoked his asylum, and is now also fighting a US extradition warrant relating to the release by WikiLeaks of a huge cache of official documents.

The US indictment charges Assange with “conspiracy” for working with former US Army intelligence analyst Chelsea Manning to crack a password stored on Department of Defence computers in March 2010.

EU 'must take action'

Dagdelen urged Britain and the EU to block any extradition request.

“We call on the British government not to extradite Julian Assange to the USA.

“The European Union must take action to protect a politically-persecuted publisher and journalist,” said the German politician, calling on Spain and her home country to grant Assange asylum.

SEE ALSO: Assange: US marine spied on me in Berlin

Dagdelen said they were trying to see Assange in prison, but their application was “still pending”.

“I'm a friend of Julian Assange. He's a son, a father, a brother and a good friend,” said Dagdelen.

“His whole life he sacrificed for the truth.”

They also accused the Ecuadoran government of “engaging in a disinformation and slander campaign against Assange” after a series of reports emerged detailing his increasingly disfunctional relationship with embassy staff.

Belmarsh has frequently been used in high-profile national security cases, including that of former Finsbury Park Mosque hate preacher Abu Hamza, who now resides in a US “supermax” prison following extradition.

Radical cleric Anjem Choudary, who was convicted in 2016 of encouraging support for the Islamic State group, spent some of his sentence there.

Belmarsh earned the moniker “the UK's Guantanamo Bay” in the period following the 9/11 attacks after it was used to detain a number of people under anti-terror laws.