Kabul, Afghanistan ? The Obama administration on Thursday endorsed fragile Afghan efforts to negotiate peace with the Taliban, backing off its prior stance that talks with the Taliban were premature until the war is all but won.

U.S. Defense Secretary Robert Gates, who only last month had said it was too soon for high-level reconciliation talks, struck a different chord at NATO headquarters in Brussels, Belgium.

“Whenever opportunities arise that are worth exploring, I think we ought to take advantage of that,” Gates said.

Senior U.S. officials have long said they didn’t expect the Taliban to talk peace as long as the militants believed they were winning, and at least some administration officials had been cool to peace feelers put forth by President Hamid Karzai.

The new acceptance of reconciliation could be seen as an admission that the war is going badly. Or it may reflect the view of U.S. military commanders that NATO troops have damaged the insurgency following the surge of more than 30,000 U.S. forces ordered by President Barack Obama.

Some administration officials recently said stepped-up NATO operations, as well as U.S. drone attacks on militants across the border in Pakistan, have shaken the Taliban enough to coax them into negotiations.

Publicizing U.S. support for any peace talks also could be a sign that the administration is looking for ways to demonstrate a commitment to ending the war short of calling home large numbers of troops. The war has claimed the lives of more than 2,000 NATO troops, including at least 1,228 Americans. Gates spoke on a day that eight NATO service members were killed across Afghanistan.

There have been no formal negotiations yet between the Afghan government and the Taliban, only some contacts and signals, according to the Afghan government.

Former Afghan President Burhanuddin Rabbani, leader of the country’s newly formed peace council, said Thursday that the Taliban have not completely rejected a peaceful resolution of the war.

“They have some conditions to start the negotiations process,” he told a news conference. “It gives us hope that they want to talk and negotiate.”

Those conditions are believed to include U.S. first releasing Taliban prisoners from Guantanamo Bay and the U.N. removing scores of militants from its sanctions list.

A senior NATO official said that coalition forces are now allowing safe passage for top Taliban leaders to attend talks — some of them in Kabul.

But Taliban representatives insisted Thursday they will not negotiate so long as foreign troops occupy their country, saying no one who speaks for the group is in talks with the Afghan government.