"The war effort continues," Pentagon press secretary George Little told reporters as US officials said that Shamsi air base in Pakistan was not critical to carrying out drone strikes.
Asked how long US and NATO forces could operate in Afghanistan without supplies coming in through Pakistan, Little said: "It's important to focus on the war effort. Every one realises we have an enemy to enage in Afghanistan and the US military is prepared to carry on."
His remarks are significant as nearly half the NATO forces supplies run through routes in Pakistan which have been closed by the Pakistan government after last weekend's lethal air raid.
After the strike, Islamabad also ordered the US to vacate within 15 days the Shamsi air base in Balochistan, which is believed to be used for drone-operations against militants inside Pakistan.
The remote Shamsi air base is reportedly used as a drone hub by the CIA, but US officials said these operations will not be jeopardized if Islamabad goes ahead with expelling Americans from the key base.
The American official said that if Pakistan makes good its threat to close down the base, the move would be largely be symbolic as US forces were now using bases in Afghanistan to hit Taliban linked groups inside Pakistan.