The 41-year-old, who was recommended for transfer in January 2010 by the Guantanamo Review Task Force, was originally brought to Guantanamo Bay in January 2002.
"In accordance with statutory requirements, the secretary of defense informed Congress of the United States' intent to transfer this individual and of the secretary (of defense)'s determination that this transfer meets the statutory standard," a Pentagon statement said.
"The United States is grateful to the government of Italy for its humanitarian gesture and willingness to support ongoing US efforts to close the Guantanamo Bay detention facility. The United States coordinated with the government of Italy to ensure this transfer took place consistent with appropriate security and humane treatment measures."
A total of 78 inmates now remain at Guantanamo, which Obama took action to begin closing in one of his first acts as president. Yemenis account for the biggest group of detainees.
Obama has been unable to fulfill his long-held campaign promise due to opposition from the Republican-held Congress, concerns at home over plans to hold one-time terror suspects on US soil and the reluctance of allies to take in the prisoners.
Some of those concerns have crystallized in recent days after the disappearance of a former Guantanamo inmate in Uruguay, where he had been resettled in 2014 along with five other ex-detainees.
Jihad Diyab - a 44-year-old Syrian - went off the South American country's radar several weeks ago after apparently evading border controls and crossing into Brazil.
According to US government statistics, about 13 percent of prisoners freed from Guantanamo since Obama began his first term have returned to violent extremism or are believed to have done so, down from 35 percent under his predecessor George W. Bush.
Paul Lewis, the Pentagon's special envoy for Guantanamo closure, said that 14 ex-prisoners have gone on to participate in attacks that killed Americans.
In February, with less than a year left in his term, Obama released a last-ditch plan to close the facility, hoping to speed up the resettlement of all but 46 of the remaining prisoners, for whom he hopes to find alternate, secure detention centers in the United States.
All those he is seeking to resettle abroad have been deemed eligible for transfer.