Nato's commander in Afghanistan, Lt Gen David Richards, has held talks with Pakistani President Pervez Musharraf on fighting terrorism.
Gen Richards fears Afghans may begin supporting the Taleban
A Pakistani spokesman said talks focused on increasing co-operation.
The meeting came amid claims that Pakistan's spy agency, ISI, is helping the Taleban, which Pakistan denies.
Gen Richards has warned that the majority of Afghans may start to support the Taleban unless their lives improve in the next six months.
Pakistani military spokesman Major General Shaukat Sultan said discussions during the hour-long meeting covered ways of increasing co-operation between the two sides in fighting terrorism.
"He [Gen Richards] has come here to discuss Nato's expanding role in Afghanistan and security co-operation between the important partners in the war on terror," he told the AFP news agency.
Ahead of his meeting with the Pakistani President, Gen Richards reportedly told a television news channel that more could be done to fight terrorism.
According to Reuters news agency, he told Geo television: "Yes, we all want to do more because we still have a problem.
"Lots of other people can do more as well - the people who I'm working with in Afghanistan and the international community."
Gen Richards assumed responsibility for foreign military operations across the whole of Afghanistan from the US-led coalition last week.
Nato forces in the south are facing mounting casualties as they engage in fighting with a resurgent Taleban.
The allegations over ISI support for the Taleban resurfaced at the end of September.
A leaked document prepared by an official in the Defence Academy, a think tank linked to the UK Ministry of Defence (MoD), said the ISI indirectly backed terrorism by supporting religious parties in Pakistan.
The MoD says the views included in the paper are not those of the author, the think-tank or the British government.
Gen Musharraf denied the allegations and said Pakistan was doing an "excellent job" in tracking down militants.
Tuesday's meeting comes after President Musharraf suggested during his recent US tour that a "counter-strategy" may be needed in Afghanistan - which was regarded as an attempt to accommodate the Taleban.
The BBC's Ilyas Khan in Karachi says this option has been favoured by the president since the government's agreement with the tribal militants in the North Waziristan area of Pakistan on 5 September.
Gen Musharraf has been publicly urging the Afghan government to replicate the agreement in the country's troubled south.
However, the Afghan government and western diplomats are reported to be lukewarm towards the plan.
Afghan President Hamid Karzai has said he wants to hold a jirga (council) of Pashtun tribes from Pakistan and Afghanistan to end Taleban violence.
Afghan officials have frequently accused Pakistan of not doing enough to stop cross-border incursions by militants, charges Pakistan denies.
In the latest violence, police in the eastern province of Nangarhar say several people including regional officials were killed in a bomb blast on Monday morning.
On Sunday night, clashes were reported in Urzgan which according to local police left at least 50 Taleban insurgents dead.