Lawyers for Britons held at a US base in Cuba have renewed "as a matter of urgency" their call for the British government to secure the men's return.
Moazzam Begg (left) and Feroz Abassi are still in US custody
Their demand was issued after the return from Guantanamo Bay of US lawyer Gitanjali Gutierrez, who met
the detainees for the first time.
Moazzam Begg from Birmingham and Londoner Feroz Abbasi are among those being held as suspected terrorists.
The US lawyer is barred from telling her UK colleagues about the visit.
Ms Gutierrez met each of her clients four times at Camp Echo during a week-long trip.
But restrictions placed upon her as a condition of counsel access prevent her from sharing details of her visit with the clients' British lawyers and families.
Despite repeated requests, the US Department of Defence has refused to permit lawyers from the UK to meet either Mr Begg or Mr Abbasi.
The pair are represented in the UK by lawyers Louise Christian and Gareth Peirce,
Ms Christian said: "The visit in no way alleviated our concerns that Mr Abbasi and Mr Begg are being denied the most rudimentary elements of justice."
Ms Peirce added: "We have learnt nothing that might reassure us.
"What we already know demands their immediate extraction from a process that has been deliberately constructed to apply maximum intense physical and mental pressure, in total isolation, from which there has been not a minutes relief for now two and a half years.
"Every additional day in Guantanamo Bay compounds the illegality of their detention. Once a process of coercive interrogation has been initiated, no subsequent steps can ever give it retrospective legitimacy."
Mr Begg and Mr Abbasi have been held in solitary confinement at "Camp Echo" since July 2003. Mr Begg has been held in total isolation since January 2002.
Michael Ratner, president of the Centre for Constitutional Rights in New York, which has been helping in the detainees' representation, said, "We entirely concur with the views of our British colleagues that there is no justice to be found in Guantanamo, and endorse their urgent call for the return of the British
detainees to the United Kingdom."