Five Taliban detainees held at the US Guantanamo Bay military prison have agreed to be transferred to Qatar, a move Afghanistan believes will boost a nascent peace process, Afghan President Hamid Karzai's spokesman has said.
The inmates told a visiting Afghan delegation they were willing to be transferred to the Gulf state, and it was now up to the US whether they were freed, said Aimal Faizi.
Washington was quick to caution that no decision had been made on a transfer.
Caitlin Hayden, a White House spokeswoman, said: "The United States has not decided to transfer any Taliban officials from Guantanamo Bay."
If agreed by Washington, the move would be seen as part of US efforts to bring the Taliban to the negotiating table to avoid prolonged instability in Afghanistan after foreign combat troops leave the country at the end of 2014.
The annoucment comes ahead of a trip to Qatar by Zalmay Rasool, the Afghan foreign minister, who will discuss reconciliation efforts with the Taliban.
"We are hopeful this will be a positive step toward peace efforts," Faizi told the Reuters news agency, adding the Taliban detainees would be reunited with their families in Qatar if the transfer takes place.
Such a good-faith measure could set in motion the first substantial political negotiations on the conflict in Afghanistan since the Taliban government was toppled in 2001 in a US-led invasion.
A year after it was unveiled, Washington's attempt to to broker an end to a war that began as the response to the September 11, 2001 al-Qaeda attacks on the US has seen little progress.
The peace drive also presents risks for US president Barack Obama months before a presidential election, as his government considers backing an arrangement that would give some degree of power to the Taliban, known for their brutality and extreme interpretation of Islam.
Despite months of covert diplomacy, it remains unclear whether the prisoner transfer will go ahead as doubts grow about the Taliban leadership's willingness to weather possible opposition from junior and more hardcore members who appear to oppose negotiations.
Ibrahim Spinzada, a senior aide to Karzai, visited the Guantanamo facility this week to secure approval from the five Taliban prisoners to be moved to Qatar.
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Karzai's government had demanded the five former senior members of the Taliban government, held at Guantanamo Bay for a decade, gave their consent before they are transferred to Qatar's custody.
US officials hope the peace initiative will gain enough traction to enable Obama to announce the establishment of fully-fledged political talks between the Karzai government and the Taliban at a NATO summit in May.
That would mark a major victory for the White House and might ease some of the anxiety created by NATO nations' plans to gradually pull out most of their troops by the end of 2014, leaving an inexperienced Afghan military and fragile government to face a still-formidable Taliban.
The Taliban detainees are seen by some US officials as among the most dangerous inmates at Guantanamo.
Their possible transfer has drawn attacks from US politicians from both parties, even before the administration
formally begins a required congressional notification process.
Among the prisoners who may be sent to Qatar is Mohammed Fazl, a "high-risk" detainee alleged to be responsible for the killing of thousands of minority Shia Muslims between 1998 and 2001.
They also include Noorullah Noori, a former senior military commander; Abdul Haq Wasiq, a former deputy intelligence minister; and Khairullah Khairkhwa, a former interior minister.
The Taliban announced in January they would open a political office in Qatar, suggesting they may be willing to engage in negotiations that would likely give them government positions or control over some of their historical southern heartland.