WASHINGTON, april 20: American commanders in Afghanistan have in recent months urged a widening of the war that could include American attacks on indigenous Pakistani militants in the tribal areas inside Pakistan, according to United States officials.

The requests have been rebuffed for now, the officials said, after deliberations in Washington among senior Bush administration officials who fear that attacking Pakistani radicals may anger Pakistan’s new government, which is negotiating with the militants, and destabilise an already fragile security situation.

American commanders would prefer that Pakistani forces attack the militants, but Pakistani military operations in the tribal areas have slowed recently to avoid upsetting the negotiations. Pakistan’s government has given the CIA limited authority to kill Arab and other foreign operatives in the tribal areas, using remotely piloted Predator aircraft. But administration officials say the Pakistani government has put far greater restrictions on American operations against indigenous Pakistani militant groups, including one thought to have been behind the assassination of former Prime Minister Benazir Bhutto.

American intelligence officials say that the threat emanating from Pakistan’s tribal areas is growing, and that Pakistani networks there have taken on an increasingly important role as an ally of al-Qaeda in plotting attacks against American and other allied troops in Afghanistan, and in helping foreign operatives plan attacks on targets in the West. The officials said the American military’s proposals included options for limited cross-border artillery strikes into Pakistan, missile attacks by Predator aircraft or raids by small teams of CIA paramilitary forces or Special Operations forces.

Officials say the risk of angering the new government in Pakistan and stirring increased anti-American sentiment in the tribal areas outweighs the benefits of dismantling militant networks. “It’s certainly something we want to get to, but not yet,” said an official.