Nato foreign ministers meeting in Brussels have agreed to step up their military and economic assistance to Afghanistan, officials have said.
US-led forces have been fighting the Taleban since 2001
The decision came as the US pledged an extra $10.6bn (£5.4bn) to bolster its Afghan effort and retain troops there.
US Secretary of State Condoleezza Rice said Nato "must take a hard look" at what more it can do for Afghanistan.
Nato's top commander meanwhile has said his forces will mount a spring offensive against the Taleban.
Officials from the alliance have warned they expect Taleban fighters in Afghanistan to intensify attacks when the weather begins to warm up.
Separately, Nato said it may have killed a "senior Taleban leader and his deputies" in southern Helmand province.
The BBC's Rob Watson in Brussels says the announcement of the new US aid package for Afghanistan was clearly intended to challenge Nato's European members to do more as well.
The strategy appears to have had some success, he says.
According to Nato officials, foreign ministers have signalled a willingness to provide more money and support for Afghanistan.
"Allies are going to step up their civilian, military and economic efforts, with increased pledges for funding... and more forces on the ground," AFP news agency quoted Nato spokesman James Appathurai as saying.
Speaking after the meeting, Nato Secretary General Jaap de Hoop Scheffer said he was "relatively optimistic that other nations will step up to the plate".
But our correspondent says there are no specific commitments as yet .
Ms Rice told delegates all would share in the benefits of Afghanistan's success so all must share in the burdens.
On Thursday the secretary of state said the US planned to spend an additional $8.6bn on security, including training and equipping Afghan forces, while $2bn would go towards reconstruction.
It is a big funding increase over the $14bn the US has spent in Afghanistan since 2001.
Earlier the Pentagon said 3,200 men of the 3rd Brigade, 10th Mountain Division would remain in the country for an extra four months after their tour of duty was meant to end next month.
The US has 24,000 troops in Afghanistan - more than other Nato nations put together.
'Leading Taleban killed'
US Assistant Secretary of State Richard Boucher told the BBC the Taleban were expected to intensify their attacks in the coming months.
"I think we will face a strong offensive and will have a difficult and dangerous and bloody spring," he said.
However Nato's top commander, Gen John Craddock, said the alliance planned to take the initiative against the Taleban and was currently preparing for a spring offensive.
Meanwhile Nato said a "senior Taleban leader and his deputies are believed to have been killed" in an air strike in the Musa Qala district of Helmand province on Thursday.
It has not named the man but said "precision-guided munitions impacted the target, completely destroying the compound".
Also on Friday a suicide bomber triggered explosives outside a US-funded aid office in Helmand's capital, Lashkar Gah, killing himself and wounding at least one policeman, provincial officials said.
MAIN FLASHPOINTS IN AFGHANISTAN
There are 32,500 Nato-led troops in Afghanistan
Main troop contributors: US, (11,800), UK (6,000), Germany (2,700) Canada, (2,500) Netherlands (2,000), Italy, (1,800) and France (975)