MIAMI - A man from Yemen who spent the past 14 years in custody at Guantanamo Bay has been freed and sent to the Balkan nation of Montenegro, the Pentagon said Wednesday, marking the start of what is expected to be a new round of releases from the U.S. base in Cuba.

U.S. officials cleared Abdel Malik Abdel Wahab al-Rahabi for release in December 2014 after an intensive security review. But the Obama administration does not send Guantanamo prisoners back to Yemen because of the civil war there and the government had to find another country to accept him for resettlement.

This was the second prisoner this year resettled in Montenegro amid a renewed push by the administration to at least whittle down the number of men held at Guantanamo even as Congress continues to prevent the closure of the detention centre in Cuba with a prohibition on transferring prisoners to the U.S.

The U.S. government is grateful to Montenegro for accepting the former prisoner, said Lee Wolosky, special envoy for Guantanamo closure at the State Department.

"Montenegro now joins other U.S. friends and allies in Europe in accepting multiple detainees for resettlement, bringing us closer to our shared goal of closing the facility," he said.

There are now 79 prisoners at Guantanamo, including 29 who have been cleared to be sent home or to other countries for resettlement. Officials expect to release most of those cleared in the coming weeks, leaving mostly men who have been charged or convicted by military commission for war crimes or who authorities believe are too dangerous to release.

The U.S. opened the detention centre in January 2002 to hold foreign fighters suspected of links to the Taliban or the al-Qaida terrorist organization. At its peak, the facility held about 680 prisoners. There were 242 when Obama took office pledging to close the detention centre within a year.

Al-Rahabi had been at Guantanamo since shortly after it opened. A Pentagon profile released before he appeared before a review board in 2013 said he had travelled from his homeland to Afghanistan and "almost certainly" became a member of al-Qaida. But he was never charged with a crime, and authorities ultimately decided he did not pose a security threat and could be released.

While in custody, al-Rahabi studied English, worked with military officials to help ease tensions in the detention centre and worked with several fellow prisoners on an extensively detailed plan for a post-Guantanamo agricultural enterprise, the "Yemen Milk and Honey Farms Limited," according to his lawyer, David Remes.

He was desperate to get out of Guantanamo and reunite with his wife and daughter. "He's been waiting for this for a long time," Remes said.

The lawyer, who has represented more than two dozen prisoners at Guantanamo over the years, said there has been a notable sense of relief among men he has met with at the base in recent weeks.

"It's no longer a question of whether, or even a question of when, it's a question of how soon," Remes said.