Lawyers for Omar Khadr, a Canadian-born prisoner at Guantanamo Bay, have said they are negotiating to avert a trial.
Mr Khadr, whose father allegedly helped finance al-Qaeda, is the youngest detainee at Guantanamo. He was captured in Afghanistan in 2002 when he was 15.
A Canadian government spokesman said the deal rumours were "not correct" while US officials declined to comment.
But Mr Khadr's lawyer, Nathan Whiting, claimed that the negotiations were "ongoing".
"We're hopeful that there is going to be a deal. There isn't one yet," Mr Whiting said.
Mr Khadr's trial began in August but was delayed when his lawyer fell ill. The trial is due to reconvene on Monday at the Guantanamo Bay detention facility.
Mr Khadr, now 24, has pleaded not guilty to charges including murder, conspiracy and spying, and could face life imprisonment if convicted.
The US government alleges that he threw a grenade that killed an American soldier. Prosecutors have also accused him of having close family ties with Osama bin Laden.
Mr Khadr's lawyers argue that his family forced him into the war as a child
Canadian Prime Minister Stephen Harper has refused to ask US authorities to release Khadr, who is the only remaining Western citizen at Guantanamo.