FACTBOX: Will Pakistan open new fronts against Taliban?

(Reuters) - Pakistan may open new fronts against the Taliban in its ethnic Pashtun tribal belt on the Afghan border after the government said its forces had captured militant strongholds in their South Waziristan bastion.

U.S. Central Command chief General David Petraeus, in Islamabad for talks, was expected to reiterate a U.S. call for Pakistan to expand its battle through its lawless northwest, a global hub for al Qaeda and allied groups, as President Barack Obama's administration struggles to stabilize Afghanistan.

Here are some questions and answers about Pakistan's battle against militants.

WHAT HAVE PAKISTANI FORCES ACHIEVED?

Pakistani forces launched an offensive against the Taliban in the Swat valley in late April amid fears that militants were moving closer to the capital, Islamabad. Swat is about 120 km (80 miles) northwest of Islamabad. The military has cleared most of the former tourist valley but faces pockets of resistance.

Buoyed by success in Swat, the army mounted an offensive in South Waziristan, a major sanctuary of al Qaeda and the Taliban on the Afghan border, in mid-October.

The offensive was the army's biggest in years involving 30,000 soldiers. It says nearly 800 militants and 80 soldiers have been killed. There has been no independent verification of the toll.

Government forces have captured most militant strongholds in South Waziristan but security officials say many militants and their leaders have melted away into nearby tribal areas, including North Waziristan, Orakzai and Kurram.

Militants have hit back with a wave of bombs in towns and cities that have killed hundreds of people.

WHAT NEXT?

Prime Minister Yusuf Raza Gilani hinted on Saturday that the army might shift its focus to Orakzai, southwest of the main northwestern city of Peshawar. The city has borne the brunt of militant bomb attacks.

Orakzai is a major base of Hakimullah Mehsud, a militant commander who became the head of the Pakistani Taliban after his predecessor, Baitullah Mehsud, was killed in a missile strike by a pilotless U.S. drone in South Waziristan in August.

Intelligence officials say paramilitary forces have been cracking down on militants in Orakzai as well as neighboring Kurram for several weeks. Aircraft have also been attacking.

WHAT DOES THE U.S. WANT?

The United States has praised action against the militants attacking the Pakistani state but it is also pressing Islamabad to go after the Taliban factions fighting in Afghanistan out of Pakistani border enclaves.

Announcing his strategy for the eight-year-old war in Afghanistan, Obama said this month the United States would not tolerate militant havens in Pakistan and urged it to fight the "cancer" of extremism.

Two main Afghan Taliban factions are based in North Waziristan. An Afghan Taliban leadership council known as the Quetta shura is based in the southwest, U.S. officials say.

But security analysts say the government is unlikely to take action against Afghan Taliban groups for now as its hands are full with the fight against the Pakistani Taliban.

Some analysts also say Pakistan is unlikely to provoke the Afghan Taliban as some Pakistani elements consider them a safe bet for pursuing a long-term goal of a friendly Kabul government and minimizing old rival India's influence in Afghanistan.

(Editing by Robert Birsel)