The new coalition government has summoned the national assembly, or lower house of parliament, to sit on August 11 and could begin the impeachment proceedings then, a senior official said. President Musharraf’s allies have previously said he would fight any attempt to topple him.

The objectives of the war in Afghanistan have become increasingly uncertain in a conflict where Taliban leaders say they do not feel the need to control territory, at least for now, or to outfight American and NATO forces to defeat them — only to outlast them in a region that is in any case their home.

The American officials also said there was new information showing that members of the Pakistani intelligence service were increasingly providing militants with details about the American campaign against them, in some cases allowing militants to avoid American missile strikes in Pakistan’s tribal areas.