Julian Assange’s lawyers have complained prison officers stopped them spending adequate time with their client as the Wikileaks founder appeared in court ahead of his extradition hearing.

Mr Assange saluted supporters in a packed public gallery at Westminster Magistrates Court for a 12-minute hearing – speaking only to confirm his name and to briefly state he did not understand an element of the proceedings.

The hearing was adjourned for the remainder of the day after lawyer Gareth Peirce said she had been unable to spend sufficient time with her client and go through his evidence during a visit to HMP Belmarsh.

The 48-year-old is being held at the high-security prison as he awaits the outcome of an extradition request from the US, where he faces 18 charges brought forward by the Donald Trump's justice department including conspiracy to hack a Pentagon computer.

Ms Peirce said "We have pushed Belmarsh in every way - it is a breach of a defendant's rights."

Key moments for Julian Assange Show all 9 1 /9 Key moments for Julian Assange Key moments for Julian Assange The situation today Assange was arrested after Metropolitan Police officers were invited into the Ecuadorian embassy on April 11 2019. How did it come to this? Ruptly TV Key moments for Julian Assange The break Assange shows the front page of the Guardian on July 26 2010, the day that they broke the story of the thousands of military files leaked by WikiLeaks AFP/Getty Key moments for Julian Assange Wanted A warrant for Assange's arrest was issued in August 2010 for counts of rape and molestation in Sweden AFP/Getty Key moments for Julian Assange Ruling The UK's Supreme Court ruled in 2012 that Assange should be extradited to Sweden to face trial Getty Key moments for Julian Assange Sanctuary Following the ruling, Assange was given asylum by the Ecuadorian governement over fears that his human rights would be violated if he were extradited, he has since remained in the embassy in London Getty Key moments for Julian Assange A friend in Pam Friend Pamela Anderson delivers lunch to Assange at the embassy in October 2016. She has since spoken against his arrest Getty Key moments for Julian Assange Arbitrarily detained A UN panel found in 2016 that Assange had been arbitrarily detained and that he had not been able to claim his full right to asylum. It urged Sweden to withdraw the charges against him Getty Key moments for Julian Assange The cat ultimatum Last year, the Ecuadorian embassy threatened to revoke Assange's internet access unless he stopped making political statements online and started taking better care of James, his pet cat. Assange accused Ecuador of violating his rights Reuters Key moments for Julian Assange Arrest Assange was arrested on April 11 2019. Ecuador revoked his asylum status and invited the Metropolitan Police in to the embassy to arrest him. Reuters

Wearing a black jacket, grey jumper and glasses, Mr Assange slowly raised his right fist as he was led to the court’s holding cells to further discuss his case and sign off on evidence.

Among those supporting him at court was rapper MIA, who attended proceedings a day before she is due to receive an MBE for services to music.

“I think it was important to follow this case. I am off to get a medal at Buckingham Palace tomorrow and I think today is just as important," she told reporters outside court. "To give somebody an hour to put their case together is not right."

Mr Assange was arrested at the Ecuadorian embassy in London in April, having claimed asylum in the building for seven years to avoid extradition to Sweden over sex offence allegations - which he has always denied.

Sweden has since dropped its investigation into Mr Assange because of the lenght of the time which has passed the claims were first made, but he still faces a string of charges in the US.

Many of the charges relate to Mr Assange’s founding and work on Wikileaks - which published sensitive and classified documents, including more than a million files leaked by US army intelligence analyst Chelsea Manning.

Human rights organisations have raised concerns over the duration of Mr Assange’s incarceration, including his time spent at HMP Belmarsh and in the Ecuadorean Embassy.

In May, Nils Melzer, the UN’s Special Rapporteur on torture, condemned the “deliberate, concerted and sustained nature of the abuse inflicted on Mr Assange”.