NATO Secretary General Jaap de Hoop Scheffer was in Kabul on Thursday for talks with Afghan and alliance officials on the Taliban insurgency and reconstruction, a NATO spokesman said.
Scheffer, who arrived here on Wednesday, was likely to meet Afghan President Hamid Karzai and other government officials late on Thursday, NATO spokesman Nicholas Lunt said.
The alliance's chief has already met with US General Dan McNeill, the commander of the 37-nation, NATO-led International Security Assistance Force, Lunt said.
The Secretary General is also due to meet some non-governmental organisations and to travel to some outlying Afghan provinces before his three-day visit ends, Lunt added.
"He'll go around the country before leaving," Lunt said, but would not give details because of security reasons.
NATO has more than 35,000 troops in Afghanistan operating under a UN-mandated peacekeeping mission.
Many are based in the south and east where Taliban militants are active.
Last week NATO military chief US General Bantz Craddock warned that the alliance's members were putting the lives of their soldiers in danger in Afghanistan by refusing to provide enough troops to fight off the Taliban.
An insurgency by the fundamentalist Taliban claimed more than 4,000 lives in 2006, making it the deadliest year in Afghanistan since US-led forces ousted the Islamic regime five years earlier.