Pakistan's ambassador to the United States defended his country's blockade of a NATO supply line Sunday and hinted it was triggered by uncertainty in his government over whether Pakistan and the US are on the same side in the war against the Taliban.

Appearing on CNN's State of the Union, Husain Haqqani said he expected the supply line to be re-opened within a week, once public anger over a series of NATO helicopter incursions into Pakistan died down.

"We can't take the risk of letting convoys pass at a time when people are enraged, [when] there are tribal people there who are not necessarily fully under the control of the Pakistani government," he said.

Haqqani added: "Allies have to reassure each other that if they kill the personnel of the other side, it was basically because of the fog of war, and not because of any deliberate action. And that's important, and the Americans have assured us of that."

Haqqani was referring to an incident Thursday in which a NATO helicopter attack killed three Pakistani soldiers in Pakistan's northwest. In response, the Pakistani government ordered a halt to convoys of NATO supply material running through the Khyber Pass into Afghanistan. It also warned Western countries that it would stop protecting its supply lines if such attacks occurred again.

While some analysts saw that as an empty threat, other observers argued it wasn't a coincidence that, a day after the Pakistani soldiers were killed, militants torched 27 fuel tankers in a NATO supply convoy.

According to the Associated Press, some 80 percent of non-lethal supplies for the Afghanistan war effort pass through Pakistan. Haqqani noted on CNN that other supply lines into Afghanistan have remained open.

But Haqqani's assurances that the supply line will soon be open will likely not quell concerns in Washington that Pakistan is becoming an unreliable partner in the nearly decade-long effort against insurgents in central Asia.

One sign of that growing wariness came from Sen. Carl Levin, chair of the Senate Armed Services Committee, who accused Pakistani officials on Friday of being two-faced when it came to their attitude to the war.

"I had real problems with the Pakistan government publicly attacking us when we accurately hit a target, when it is clear they don't object privately," Levin said.

Levin added: "They object when we make mistakes. ... I mean we hit some Pakistani troops by mistake the other day and there is some strong blowback on that. This is understandable."

The Pakistani government has found itself walking a fine line between its commitment to the Afghan war effort and mass opposition to it inside Pakistan. A recent poll from the New America Foundation found that more than three-quarters of Pakistanis oppose US missile strikes. More Pakistanis blamed the US for the ongoing violence than blamed the Taliban.

Fifty-nine percent of respondents said that suicide bombings against Western forces were "often" or "sometimes" justified.

This video is from CNN's State of the Union, broadcast Oct. 3, 2010.

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