The Guardian reported on Monday that the US military told Sami Muhyi al-Din al-Hajj that he would be released as long as he agreed to spy on journalists at Aljazeera.
In documents seen by the Guardian newspaper, al-Hajj says US military personnel alleged during interrogation that Aljazeera has been infiltrated by al-Qaida and that one of its presenters is linked to Islamists.
The documents state some of the interviews have been carried out by British interrogators, who also wanted the cameraman to spy for them.
Al-Hajj's allegations are written in note form during visits he received in Guantanamo in June this year from his lawyer Clive Stafford-Smith.
The notes have been declassified by the US military.
The documents appear to show that the American military views Aljazeera as an al-Qaida front.
An Aljazeera spokesman said: "The allegations made by the US military are baseless ... . It is just an attempt to disparage the Aljazeera name."
Stafford-Smith told Aljazeera.net earlier this year: "The Americans have tried to make him an informant with the goal of getting him to say that Aljazeera is linked to al-Qaida."
Al-Hajj said that in one session of questioning he was offered US citizenship if he became a spy.
"Sami Muhyi al-Din al-Hajj is completely innocent ... . The only reason he has been treated like he has is because he is an Aljazeera journalist"
The Guardian said al-Hajj was told: "We will help you write a book and then we will publish it. This will help make the al-Qaida people contact you, and work with you.'"
Al-Hajj, a Sudanese national, was arrested in late 2001 while working for Aljazeera in Afghanistan.
"He is completely innocent. He is about as much of a terrorist as my granddad. The only reason he has been treated like he has is because he is an Aljazeera journalist," Stafford-Smith told Aljazeera.net.
On Tuesday, he told Aljazeera.net in an email interview: "The US needs to wake up to the fact that the most effective counter-terrorism measure is the enforcement of human rights such as the freedom of the press, rather than attempting to muzzle such freedoms by persecuting members of media networks that it disagrees with."