Pakistan's army chief, General Ashfaq Parvez Kayani, has assured NATO commanders meeting in Brussels that he will keep supply lines to their troops in Afghanistan open after a surge in attacks along the Afghan-Pakistani border.

A top NATO officer, Italian Navy Admiral Giampaolo Di Paola, told reporters afterward that Kayani also urged the alliance to work with local tribal leaders, rather than just trying to seal off the border through force, which he said cannot be done.

General Kayani's presence at the meeting indicates how interlinked security developments in Pakistan have become with those in neighboring Afghanistan, where NATO has about 70,000 troops.

Pakistani and NATO officials say they are pooling their efforts to fight militants on both sides of the border. They say the ongoing "Operation Lionheart" involves U.S.- led coalition forces in Afghanistan giving assistance to Pakistani troops fighting militants in Pakistan's tribal district of Bajaur.

Afghan, Pakistani and NATO leaders say restoring security to the border region is vital to Afghanistan's success and Pakistan's stability.

The Secretary General of NATO, Jaap de Hoop Scheffer, on Tuesday called for deployment of more non-U.S. troops to prevent Afghanistan from becoming  a terrorist "safe haven."

The U.S. commander of NATO forces in Afghanistan, General David McKiernan, said Tuesday that he hopes the incoming administration of President-Elect Barack Obama will boost troop levels there "soon."