The US military is transferring Osama bin Laden's former driver, Salim Hamdan, from the US naval base in Guantanamo Bay to his home country of Yemen, The Washington Post has reported citing two government officials.
He is expected to arrive within 48 hours in Yemen's capital, Sanaa.
But military prosecutors and Hamdan's attorneys on Monday said they could not confirm his impending transfer, the daily said.
Hamdan is to serve out the remaining month of his military commission sentence in a Yemeni prison, the newspaper said.
A military commission in August this year convicted Hamdan of supporting terrorism but acquitted him on more serious charges of conspiring with al-Qaeda to wage murderous attacks, in the first US war crimes trial since World War II.
Hamdan was convicted of providing personal services in support of terrorism, specifically driving, guarding and ferrying weapons for a man he knew to be the leader of al-Qaeda.
Hamdan was captured in November 2001 at a roadblock in Afghanistan, not long after the US invasion that followed the September 11 attacks.
Held as a suspected terrorist at the Guantanamo prison camp, he won a supreme court case in June 2006 that struck down the Bush administration's first trial system there and prompted congress to rewrite the rules.
The Guantanamo trial was the first full test of the military tribunal system authorised by the Bush administration to try foreign captives on terrorism charges outside the regular US court system.
Hamdan's attorneys said the ruling made clear the detainees are entitled to fundamental constitutional rights.