Nato's top official has joined the US and France in calling for Afghan forces to take the lead in all combat operations by mid-2013, while continuing to help in fighting the Taliban.
Both US Defence Secretary Leon Panetta and French President Nicolas Sarkozy have suggested in recent days that the coalition should gradually move out of combat in 2013.
Government forces are supposed to assume responsibility for the war at the end of 2014, when the coalition is expected to end its participation in the war.
The 2014 date was adopted by Nato leaders at a summit in Lisbon in November 2010. Until now, it was widely assumed that coalition forces would remain in a combat role until the end of 2014.
Speaking to reporters before a two-day meeting of Nato defence ministers in Brussels, Nato Secretary-General Anders Fogh Rasmussen said Afghanistan remains the alliance's top operational priority, and that the coalition has been making progress in the war.
He said transition to Afghan security control, which started last year, will continue through mid-2013 with the Afghan army and police gradually taking the lead in all regions of the country.
"From that time the Afghan security forces are in the lead all over Afghanistan, and from that time the role of our troops will gradually change from combat to support," he said.
This process will conclude at the end of 2014, when government forces are scheduled to assume full responsibility for security in the entire country, Fogh Rasmussen said. The allies are working on the details of a longterm partnership with Afghanistan.
"But Afghans will not be left alone at the end of the transition process. We are committed to providing support to Afghanistan through transition and beyond," Fogh Rasmussen said.
Speaking to reporters on the flight to Brussels, Panetta said: "Hopefully by the mid to latter part of 2013 we'll be able to make a transition from a combat role to a training, advise and assist role."
He added that this "doesn't mean we're not going to be combat-ready," but rather that the US and other international forces will no longer be in "the formal combat role we're in now."
The ministerial meeting comes a day after a secret Nato report was leaked to the media suggesting that insurgent morale remains extremely high after more than a decade of war and that the Taliban remain confident they will defeat the coalition.
It also follows a series of attacks by members of Afghan forces on Nato troops or advisers.