Trial proceedings were set to resume on Monday for Canadian inmate Omar Khadr, the last Westerner at the US prison at Guantanamo, amid a flurry of activity that could lead to a plea agreement.
The trial for 24-year-old Canadian, appearing before the revamped military tribunal set up by US President Barack Obama, resumes after a suspension in August when military defense lawyer Jon Jackson collapsed.
"There is a trial tomorrow and there is no deal in place at this particular moment," Khadr's lawyer Dennis Edney said.
"Omar is nervous and tense. He is confused," Edney told reporters in Guantanamo. "He tries to understand why US President Obama has received the Nobel Peace Prize... and yet he's still here when hundreds and hundreds of detainees have been released."
Khadr was just 15 when he was arrested for allegedly throwing a hand grenade that killed a US sergeant during a 2002 attack in Afghanistan.
He has been charged with murder in violation of the laws of war, conspiracy and espionage. If he is found guilty, he could be sentenced to life in prison.
Canadian Prime Minister Stephen Harper's conservative government has steadfastly refused to seek Khadr's repatriation, saying that US proceedings should run their course, despite criticism from some opposition lawmakers.
Obama has pledged to close down the Guantanamo prison, a symbol for many of excesses under his predecessor George W. Bush. But he missed his own deadline as he struggles to find an alternative location for the inmates.
If there is a guilty plea, a military jury would be asked to determine the sentence.
If a plea deal is reached later, the jury would not be able to impose a harsher penalty than in the plea deal, and if the plea agreement is secret, the sentence may not be made public.
If the trial goes ahead, the presiding military judge, Patrick Parrish, must decide whether to accept in evidence all Khadr's statements to interrogators after undergoing several operations for his wounds in the Bagram base in Afghanistan.
Khadr's first US interrogator told the judge in May that he had threatened the boy with tales of rape and murder in US jails to make him talk. The interrogator was later court-martialed for abusing prisoners in Bagram.
In August, chief prosecutor Jeff Groharing told the seven military officers on the jury that Khadr in his own words had described himself as "a terrorist praying for Al-Qaeda," and that the youth's intention was "to kill as many Americans" as possible.
But Khadr has denied throwing the grenade that killed US sergeant Christopher Speer, with his lawyers portraying him as a frightened boy intimidated by three "bad men" who told him what to do.
Khadr's trial is the first to be heard since the military tribunals, created by former president George W. Bush, were revamped last year by the Obama administration and Congress to give greater rights to defendants.
A total of 174 prisoners remain in detention at the US base, which has received nearly 800 since being opened in 2002.
Khadr grew up in Canada, Pakistan and Afghanistan, and is the son of an Al-Qaeda official who was killed in 2003.
The youth was seriously wounded and captured after US special forces laid siege to an Al-Qaeda hideout where Khadr allegedly made improvised explosives.