A demonstration took place on Saturday calling on the Government to halt the extradition of Babar Ahmad and Syed Talha Ahsan to the United States.
Mr Ahmad's family and campaigners gathered outside the House of Commons, alongside those of Gary McKinnon and Richard O' Dwyer, who also face extradition.
The terror suspect, who along with Mr Ahsan is from Tooting, was arrested in August 2004 and has been detained without trial ever since.
Earlier this year The European Court of Human Rights backed Mr Ahmad's extradition from the UK to the US.
Ashfaq Ahmad, father of Babar Ahmad, spoke during the demonstration, which was organised by the We Are Babar Ahmad campaign.
Human rights campaigners, trade unionists and Muslim civil society groups also joined protesters.
The protest was called to rally against the controversial UK-US Extradition Treaty 2003, with a meeting taking place on June 20 to discuss the treaty.
Sadiq Khan MP said on his website: ""I am extremely concerned about Talha’s medical condition. He suffers from Asperger syndrome and after seeing the way that Christopher Tappin was treated I am concerned whether Talha would received the attention his condition requires.
"I recently arranged for the Chair of the Home Affairs Select Committee to hear directly from Babar & Talha, and he has now written to the Director of Public Prosecutions (DPP) asking further questions. "The coalition Government have promised to review the extradition agreement and this should happen as soon as possible. I will continue to do everything I can to support my constituents."