PARACHINAR, Pakistan -- A Pakistani militant commander close to the Afghan border threatened Saturday to abandon an unofficial peace deal with the government, raising the specter of more violence in the nuclear-armed country.

Hafiz Gul Bahadur cited American missile strikes and shelling by the Pakistani army as the reason for his threat, which was made in a one-page statement distributed in the town of Miran Shah in the North Waziristan region, the militant leader's main base.

"If the government continues with such brutal acts in the future, it will be difficult for us to keep our patience any longer," the statement said.

Bahadur commands up to 4,000 fighters in North Waziristan, which is under the effective control of his group and other militant organizations. He is believed to have a loose arrangement with Pakistan's army under which troops refrain from targeting him or his fighters as long as his militant group focuses its attacks only on U.S. and NATO troops across the border in Afghanistan.

Pakistan's army doesn't officially recognize the deal. Army officers were not available for comment.

If Bahadur were to make good on his threat, it could mean more bombings in Pakistani cities and pose tactical challenges for the army's stretched forces in North Waziristan and other border regions.

But the extent of Bahadur's capabilities are unclear. Moreover, Washington and domestic critics have urged Islamabad not to distinguish between militant groups in the northwest, saying they all ultimately pose a threat to the state regardless of their temporary orientation.

Pakistan's army is currently focused on fighting the Pakistani Taliban, which has declared war on the state and has carried out hundreds of suicide attacks around the country. The army says it doesn't have the capacity to tackle all the groups, and sees no need to antagonize those factions that do not pose an immediate threat to its troops.

But the arrangement is an uneasy one, and Washington -- which has given the Pakistani army billions in aid since 2001 -- wants action against Bahadur's group as well as the Afghan Taliban and its allied factions like the Haqqanis, who are also based in North Waziristan.

Bahadur's men are often targeted by American drone-fired missiles, which rain down on targets in North Waziristan every few days on average. Pakistan's army publicly protests the strikes, but privately assists in the targeting for at least some of them.

"Hundreds of our warriors have been martyred in the drone strikes coordinated by the Pakistani government," Bahadur's statement said. "We have been observing restraint. But now, the government, acting on foreign instructions, is piling on the brutality against our civilians."

Critics say that striking deals with militants in North Waziristan is wrong given that all factions there -- including international extremists affiliated with Al Qaeda -- are allied with each other and share resources, weapons and transport networks.