By David Loyn
BBC News, Islamabad
Adm di Paola expressed confidence about Pakistan's commitment
The head of Nato's military committee, Adm Giampaolo di Paola, has said that the alliance has no imperial ambitions in the Pakistan and Afghanistan region.
He said that Nato was however increasing ties with Islamabad as the war against the Taliban in Afghanistan and Pakistan escalates.
Adm di Paola said that Nato would not remain in Afghanistan if the Afghan government wanted them to go.
He said the fight against the Taliban was necessary for world security.
Pakistan's military and intelligence services had severed their links with militant groups in the region that they used to support, the admiral said.
Evidence for that could be seen in the considerable loss of military and civilian lives Pakistan was experiencing in its fight against the Taliban in its tribal areas and in the North West Frontier Pronvince.
"I feel confident that there is a clear engagement, strong engagement, an engagement they are paying with the life of their people, civilian and military, an engagement they are paying [for] with the cost of displacement, displaced people," he said.
Aid agencies estimate that about two million people have been forced to flee their homes because of fighting in north-west Pakistan. On Thursday the government announced a timetable for them to return.
Admi di Paola said that no nation would pay the kind of cost that Pakistan had if it was not seriously engaged in the fight.
He said that Afghanistan was a "tougher nut to crack than Nato countries had expected" but the fight was worth it for security in the region and in the wider world.