Weakened by a prolonged hunger strike, Yemeni detainees who have languished at Guantanamo Bay for years see growing hope of finally returning home after a ban on transfers to Yemen was lifted.

If fulfilled, President Barack Obama's pledge Thursday to end a moratorium on sending prisoners to the Gulf state would remove a key hurdle in closing the US military detention center for good.

Of the 86 inmates who have been cleared for release, most -- 56 -- are from Yemen, where Al-Qaeda has established a foothold. Overall, a total of 84 Yemenis currently live at the jail in southern Cuba, making them the largest group by nationality.

And most were captured more than a decade ago.

"More than a third of the entire Guantanamo population are cleared Yemeni men, men that the government itself says do not need to be in Guantanamo," lawyer Omar Farah of the Center for Constitutional Rights told AFP.

Their return was halted after a Nigerian man trained in Yemen tried to detonate explosives in his underwear on a flight to Detroit on Christmas Day 2009. The incident triggered fears that returned detainees could be tempted to join radical movements.

Farah said ending the ban is a step in the right direction, but Obama will have to pair words with action.

"Lifting the moratorium is an important step only if men like Mohammed al-Hamiri -- my client who is Yemeni and cleared for release and has been for many years -- are immediately processed for transfer and reunited with their families," he said.

Obama's move came amid a widespread hunger strike at Guantanamo. More than two thirds of the prison's 166 remaining detainees have refused food in a strike that began nearly four months ago to protest their indefinite jailing without charge.

Andrea Prasow, a Human Rights Watch expert on Guantanamo, also called the announcement an "important promise" of a "recommitment" to make good on Obama's years-old pledge to shutter the prison.

"Obama's decision to lift the ban on transfers to Yemen is an important one, it signals his intention to go forward with detainees transfers," Prasow told AFP.

But it remains to be seen if and when the transfers will take place.

"He needs not to say, six months down the road, that there's no official ban on transfers to Yemen but no one can go back there anyway for security reasons," Prasow said.

David Remes, who represents fifteen of the Yemenis, said his clients "hope against hope that something positive will come out of this."

But "every time we think there'd be lights at the end of the tunnel, it's been the headlight of an approaching train," said Remes, expressing hope that Obama's announcement would deliver more than just "the illusion of forward movement."

Several of Remes's clients, on hunger strike since February 6, have told him their recent treatment at the prison is inhumane, deteriorating to levels seen during their first years in detention, under then-president George W. Bush.

"I don't know why I'm being punished, I didn't even kill a chicken," detainee Yasin Ismail said, according to the lawyer.

He reported freezing temperatures in the cells and force-feeding using tubes inserted through the nose into the stomach.

"I don't want to be force-fed, but if you do force-feed me, at least do it humanely," said fellow inmate Uthman Abd al-Rahim Muhammad Uthman, according to Remes.

A third, the lawyer recounted, begged to be treated "as well as iguanas, even as well as insects."

Iguanas are a protected species in Guantanamo and killing one is punishable by a $10,000 fine.

Of the 103 prisoners on hunger strike, 32 were being force-fed as of Friday, two of whom were hospitalized, according to prison spokesman Lieutenant Colonel Samuel House.

Farah said those figures were unlikely to change because of the president's announcement.

"It's the prisoner's protest, their hunger strike, that created the urgency that compelled President Obama to speak about Guantanamo," Farah said.

"It has to be that same urgency that guides his action," he added.

"I don't expect the hunger strike to end until the president begins the immediate resumption of transfers."