Singer MIA has demanded the release of WikiLeaks founder Julian Assange after visiting him in London’s high security Belmarsh prison.

The rapper and songwriter – real name Mathangi Arulpragasam – is one of a number of celebrity supporters who have been to see Assange since he was sent to Belmarsh earlier this year after spending seven years in the Ecuadorean embassy in the capital to avoid extradition.

Asked how the whistleblower was faring, the 44-year-old musician said: “It’s difficult to describe… he shouldn’t be in there.

“I think when you know there are people outside who are criminals, and you are inside for advocating peace, while people profiting from war outside being celebrated …  it hurts.”

The singer said she believes Assange is being discriminated against.

She said: “I’ve been trying to give a yoga book to him for a month now and I come here every week trying to give him it, and it’s impossible.

“It’s very difficult even to get books in.

“To me that’s a very extreme method, where (prisoners) are denied even reading books.

Julian Assange extradition
Rapper MIA speaks to the media outside Belmarsh (Dominic Lipinski/PA)

“I wasn’t allowed to bring in sketchbooks for him to write the thoughts in his head or draw.

“I first thought that all prisoners are treated like that, where they’re not able to have any dignity or own the space in between their ears.

“I can sympathise with people who think he’s being treated unfairly… I think there is an element of discrimination.”

She added: “The bottom line is he’s in there (in jail) because he exposed some war crimes.

“We cannot make this an example for society where we penalise people for that.”

Assange, whose other visitors have included Chinese artist Ai Weiwei and actress Pamela Anderson, was jailed for 50 weeks in May for breaching bail after he was dragged from the embassy in London when the Ecuadorian government withdrew permission for him to be there.

Julian Assange extradition
Julian Assange is facing extradition to the US (Victoria Jones/PA)

He had been due for release in September after serving half his sentence but has been remanded in custody while he awaits extradition to the US to face charges linked to his alleged computer-hacking and unauthorised disclosure of national defence information.

He is due to face a full extradition hearing on February 25.

He originally took refuge in the embassy while awaiting extradition to Sweden where he was wanted in connection with sexual offence allegations.

At the time he claimed he was the subject of an American “witch hunt” and was at risk of being taken to the US if he was sent to the Scandinavian nation.

Swedish prosecutors dropped their investigation in 2017 because they were unable to proceed while he remained in the embassy but they have since said the case was being reopened.