Holbrooke said the region was a safe haven for extremists, and if destroyed, peace could return to Afghanistan in a relatively short period of time.
"If the Tribal Areas of western Pakistan were not a sanctuary, I believe that Afghanistan could take care of itself within a relatively short period of time," he said.
Holbrooke said that Pakistan was at the center of America's strategic concerns.
"If Afghanistan had the best government on earth, a drug-free culture and no corruption it would still be unstable if the situation in Pakistan remained as today. That is an indisputable fact, and that is the core of the dilemma that the Western nations, the NATO alliance, face today," he told The Wall Street Journal.
Holbrooke said it was very important to root out Taliban from Afghanistan, as the outlawed outfit, if it succeeds in Afghanistan, would provide al-Qaeda an opportunity to regroup itself to pursue its primary motive against the United States more aggressively.
He added that the United States would certainly respect the 'red lines' drawn by Islamabad regarding presence of foreign troops on its soil.
Holbrooke also downed all opinions which suggested waging a large scale war on terrorists inside Pakistan's territory.
"First of all we can't without their permission, and that would not be a good idea.
Secondly, cleaning them up in the mountains of Pakistan's tribal areas, as anyone can see from the search for al Qaeda in Afghanistan, is a daunting mission," he said