WASHINGTON - President Obama and his national security advisers are considering expanding the American covert war in Pakistan far beyond the unruly tribal areas to strike at a different center of Taliban power in Baluchistan, where top Taliban leaders are orchestrating attacks into southern Afghanistan.
According to senior administration officials, two of the high-level reports on Pakistan and Afghanistan that have been forwarded to the White House in recent weeks have called for broadening the target area to include a major insurgent sanctuary in and around the city of Quetta.
Mullah Muhammad Omar, who led the Taliban government that was ousted in the American-led invasion in 2001, has operated with near impunity out of the region for years, along with many of his deputies.
The extensive missile strikes being carried out by Central Intelligence Agency-operated drones have until now been limited to the tribal areas, and have never been extended into Baluchistan, a sprawling province that is under the authority of the central government, and which abuts the parts of southern Afghanistan where recent fighting has been the fiercest. Fear remains within the American government that extending the raids would worsen tensions. Pakistan complains that the strikes violate its sovereignty.
But some American officials say the missile strikes in the tribal areas have forced some leaders of the Taliban and Al Qaeda to flee south toward Quetta, making them more vulnerable. In separate reports, groups led by both Gen. David H. Petraeus, commander of American forces in the region, and Lt. Gen. Douglas E. Lute, a top White House official on Afghanistan, have recommended expanding American operations outside the tribal areas if Pakistan cannot root out the strengthening insurgency.
Many of Mr. Obama's advisers are also urging him to sustain orders issued last summer by President George W. Bush to continue Predator drone attacks against a wider range of targets in the tribal areas. They also are recommending preserving the option to conduct cross-border ground actions, using C.I.A. and Special Operations commandos, as was done in September. Mr. Bush's orders also named as targets a wide variety of insurgents seeking to topple Pakistan's government. Mr. Obama has said little in public about how broadly he wants to pursue those groups.
A spokesman for the National Security Council, Mike Hammer, declined to provide details, saying, "We're still working hard to finalize the review on Afghanistan and Pakistan that the president requested."
No other officials would talk on the record about the issue, citing the administration's continuing internal deliberations and the politically volatile nature of strikes into Pakistani territory.
"It is fair to say that there is wide agreement to sustain and continue these covert programs," said one senior administration official. "One of the foundations on which the recommendations to the president will be based is that we've got to sustain the disruption of the safe havens."
Mr. Obama's top national security advisers, known as the Principals Committee, met Tuesday to begin debating all aspects of Afghanistan-Pakistan strategy. Senior administration officials say Mr. Obama has made no decisions, but is expected to do so in coming days after hearing the advice of that group.
Any expansion of the war is bound to upset those in Mr. Obama's party who worry that he is sinking further into a lengthy conflict in Afghanistan, even while reducing forces in Iraq. It is possible that the decisions about covert actions will never be publicly announced.
Several administration and military officials stressed that they continued to prod the Pakistani military to take the lead in a more aggressive campaign to root out Taliban and Qaeda fighters who are attacking American forces in Afghanistan and increasingly destabilizing nuclear-armed Pakistan.
But with Pakistan consumed by political turmoil, fear of financial collapse and a spreading insurgency, American officials say they have few illusions that the United States will be able to rely on Pakistan's own forces. However, each strike by Predators or ground forces reverberates in Pakistan, and Mr. Obama will be weighing that cost.
Adm. Mike Mullen, the chairman of the Joint Chiefs of Staff, said on "The Charlie Rose Show" on PBS last week that the White House strategy review addresses the "safe haven in Pakistan - making sure that Afghanistan doesn't provide a capability in the long run or an environment in which Al Qaeda could return or the Taliban could return." But another senior official cautioned that "with the targets now spreading, an expanding U.S. role inside Pakistan may be more than anyone there can stomach."
As part of the same set of decisions, according to senior civilian and military officials familiar with the internal White House debate, Mr. Obama will have to choose from among a range of options for future American commitments to Afghanistan.
His core decision may be whether to scale back American ambitions there to simply assure it does not become a sanctuary for terrorists. "We are taking this back to a fundamental question," a senior diplomat involved in the discussions said. "Can you ever get a central government in Afghanistan to a point where it can exercise control over the country? That was the problem Bush never really confronted."
A second option, officials say, is to significantly boost the American commitment to train Afghan troops, with Americans taking on the Taliban with increasing help from the Afghan military. President Bush pursued versions of that strategy, but the training always took longer and proved less successful than plans called for.
A third option would involve devoting full American and NATO resources to a large-scale counterinsurgency effort. But Mr. Obama would be bound to face considerable opposition within NATO, whose leaders he will meet with early next month in Strasbourg, France. At the very time the United States is seeking to expand its presence in Afghanistan, many of the allies are scheduled to leave.
As for American strikes on militant havens inside Pakistan, administration officials say the Predator and Reaper attacks in the tribal areas have been effective at killing 9 of Al Qaeda's top 20 leaders, and the aerial campaign was recently expanded to focus on the Pakistani Taliban leader, Baitullah Mehsud, as well as his fighters and training camps. American intelligence officials say that many top Taliban commanders remain in hiding in and around Quetta, but some Afghan officials say that other senior Taliban leaders have fled to the Pakistani port city of Karachi.
Missile strikes or American commando raids in the city of Quetta or the teeming Afghan settlements and refugee camps around the city and near the Afghan border would carry high risks of civilian casualties, American officials acknowledge.
Thom Shanker contributed reporting from Washington, and Carlotta Gall from Islamabad, Pakistan.