The Pakistan government framed its response to the NATO air strike during an emergency meeting of the Defence Committee of the Cabinet chaired by Prime Minister Yousuf Raza Gilani.
The meeting was attended by the three service chiefs, including army chief Gen Ashfaq Parvez Kayani.
The cabinet committee decided to "close with immediate effect the NATO/ISAF logistics supply lines" and asked the "US to vacate the Shamsi airbase within 15 days", said a statement issued by the Prime Minister's House.
The move came hours after NATO helicopters and fighter jets fired at two border posts in Mohmand tribal region at 2 am.
Officials were quoted by the media as saying that 28 soldiers, including a major and a captain, were killed and 15 more injured in the air strike.
A statement issued by the army put the death toll at 24. Kayani strongly condemned "NATO/ISAFs blatant and unacceptable act" and issued orders for taking all necessary steps for "an effective response to this irresponsible act".
The Defence Committee of the Cabinet "reiterated the resolve of the Pakistani people and armed forces to safeguard Pakistans sovereignty, independence and territorial integrity at all costs", the official statement said.