Nato has announced that it will extend its mission in Afghanistan to cover the whole of the insurgency-hit country.
Nato will now command more than 30,000 troops in Afghanistan
The move will take the alliance into the eastern parts of Afghanistan and bring up to 12,000 American troops under Nato command.
A Nato official said the decision would be implemented in the next few weeks.
The announcement came as the US military said that militant attacks near the Pakistani border had tripled in some areas.
The rise in activity comes despite a peace agreement meant to end violence by pro-Taleban militants in Pakistan's North Waziristan border area.
Correspondents say the deal has increased friction with Afghanistan.
The decision to extend the alliance's security mission in Afghanistan was approved by Nato defence ministers meeting in Slovenia, spokesman James Appathurai said.
US forces already in the region will come under the Nato-led International Security Assistance Force (Isaf) command, taking the total number of troops to around 32,000.
He said the decision was a vote of confidence for the Nato mission.
"What it shows is that this operation is moving forward," he said. "I think it demonstrates considerable success."
Asked if the troops could be redeployed in the restive south, Mr Appathurai said he knew of no limits from Washington on troop movements.
The defence ministers also agreed on a plan to donate surplus military equipment to Afghanistan's armed forces, Nato Secretary General Jaap de Hoop Scheffer said.
"There were in rough numbers thousands of weapons offered up, and I believe probably millions of rounds of ammunition," the Associated Press news agency quoted US Defense Secretary Donald Rumsfeld as saying.
But Nato is still seeking commitments, particularly from European countries, to send an extra 2,500 soldiers.
"If you are a member of an alliance based on solidarity, you have to deliver," the Nato leader said. "We need to do more."
Violence in Afghanistan has increased in recent months as international troops have clashed with a resurgent Taleban.
The Afghan and Pakistani presidents accuse each other of failing to act against the militants, with Afghan leader Hamid Karzai particularly criticising Gen Pervez Musharraf's deal with pro-Taleban militants.
He says attacks have gone up and the US findings appeared to confirm this.
"There has been an increase in the activity certainly along the border region especially in the south-east areas across from Waziristan... in [Afghanistan's] Paktika and Khost provinces," Lt Col John Paradis of the US military told a news conference.
There were "in some cases two-fold, in some cases three-fold increases in the number of attacks," he said.
Mr Karzai has also suggested that Pakistan has turned a blind eye to Taleban supporters using parts of the country to train and launch attacks on Afghanistan.
Musharraf and Karzai did not shake hands
US President George W Bush hosted talks between Mr Karzai and Gen Musharraf in Washington on Tuesday in what correspondents said was an attempt to end spats between the two leaders.
But at a public appearance after the talks the two leaders did not speak to each other or shake hands.
Gen Musharraf has now had talks in the UK for talks with Prime Minister Tony Blair on security co-operation and Afghanistan.
The meeting came after Gen Musharraf angrily rejected the findings of a researcher at the UK Ministry of Defence which claimed that Pakistan's intelligence service, ISI, had indirectly helped the Taleban and al-Qaeda.
According to a Downing Street spokesman, President Musharraf was assured that the document did not reflect UK government policy and he agreed there was no need to discuss it further.