In an interview on CNN's "Late Edition" program, Powell said the current leadership of the extremist Islamic militia would not be welcome in a new government after the Taliban is defeated, "but at the same time there are many people within the Taliban movement who have not been in the leadership position, and may not have been active" who could serve in a new government.
Over the last week, senior officials representing Russia, India, Iran and Tajikistan all issued statements opposing a role for the Taliban in an Afghanistan government that would follow the defeat of the Taliban.
"The obscurantist, malevolent, extremist and violent ideologies on which the Taliban movement is based will pose a substantial danger to the stability of any broad-based, multi-ethnic government," the governments of India and Russia said in a recent joint statement.
Powell, speaking from Shanghai where he and President Bush were attending the Asia Pacific Economic Cooperation conference, said the idea of Taliban moderates remaining in an Afghan government had come from his discussions last week with Pakistan's military leader, President Pervez Musharraf.
Pakistan sponsored the Taliban in the early 1990s to place a government in Kabul that served its national interests. After the attack on the World Trade Center and Pentagon last month, Musharraf agreed to aid the United States in a fight against them, but is still under pressure from strong conservative Islamic elements in his own country and senior members of his intelligence services who actually helped install the Taliban regime.
Though the United States backs the Northern Alliance -- which is fighting for the internationally recognized government of Afghanistan defeated by the Taliban in 1996 -- it acknowledges the alliance does not represent a sufficiently broad section of the Afghan people to form workable government on its own.
The alliance is a loose coalition of local warlords and tribal leaders representing many of Afghanistan's ethnic minorities, but has no support from the Pashtuns -- the countries largest ethnic group.
In an earlier appearance from Shanghai on Fox News Sunday, Powell said the U.S. military campaign in Afghanistan will be affected by the weather and Ramadan -- the month-long Muslim period of fasting which begins in mid-November.
"I think it would be in our interest and the interest of the coalition to see this matter resolved before winter strikes and it makes our operations that much more difficult," Powell said.
Later on CNN he expanded this point: "There are some constraints that are coming in front of us in the form of winter arriving in about a month," the former Army general said, "which might change the tempo of our operations. But we also are noticing that the Northern Alliance, which we are supporting, has become more aggressive in their actions up north and moving toward Kabul."
Powell said the United States wants the Northern Alliance to take the city Mazar-i-Sharif and he expects the alliance would want to isolate Kabul. "The actual seizure of land and which cities might be the right ones to cause that to come about, I'm not sure. But certainly the Northern Alliance is on the march in the north toward Mazar-i-Sharif," Powell said.
United Press International in Tashkent, the capital of neighboring Uzbekistan reported Sunday that more than 1,000 U.S. troops stationed in the south of the country were waiting to move into Afghanistan once the alliance had captured the town, which is some 30 miles south of the border.
"These troops are waiting for Mazar-i-Sharif to fall," a source in the U.S. Embassy in Tashkent said.
U.S. forces, which have been in Uzbekistan for more than two weeks, would have a risk-free route into Afghanistan if the strategically important city falls.