A spokesman for Mr. Karzai, Waheed Omar, could not be reached for comment on Sunday.

In a speech in Kandahar on Sunday, Mr. Karzai promised local tribal elders that coalition military operations planned for the area this summer would not proceed without their approval.

“I know you are worried about this operation,” he said, adding: “There will be no operation until you are happy.”

Image In Kandahar on Sunday, Afghanistan's president, Hamid Karzai, addressed tribal elders' concerns about a planned offensive. Credit... Pool Photo by Golnar Motevalli

Given his tone in the last few days, it was unclear whether he was literally extending the elders veto power over the offensive, or merely trying to quell their fears and bring them on board.

Interviews with diplomats, Afghan analysts and ordinary Afghans suggest that the United States and other Western countries have three options: threaten to withdraw troops or actually withdraw them; use diplomacy, which so far has had little result; and find ways to expand citizen participation in the government, which now has hardly any elected positions at the provincial and district levels.

Threatening to withdraw, which Stephen Biddle, a senior fellow at the Council on Foreign Relations, called the “nuclear deterrent” option, would put the United States and other Western countries in the position of potentially having to make good on the promise, risking their strategic interest in a stable Afghanistan. Few experts think the country would remain peaceful without a significant foreign force here. Moreover, withdrawal could open the way for the country to again become a terrorist haven.

Some Western critics of Mr. Karzai believe that the West has no choice but to threaten to leave.

“There is no point in having troops in a mission that cannot be accomplished,” said Peter W. Galbraith, former United Nations deputy special representative for Afghanistan, who was dismissed after a dispute with his superiors over how to handle widespread electoral fraud and what senior U.N. officials later said was his advocacy of Mr. Karzai's removal. “The mission might be important, but if it can’t be achieved, there is no point in sending these troops into battle. Part of the problem is that counterinsurgency requires a credible local partner.”