Top U.S. officials, including Secretary of State Hillary Clinton and CIA Director David Petraeus, are due to visit Pakistan to press leaders there on confronting militants in the country's northwest tribal region.

The U.S. delegation for the talks Thursday in Islamabad will also include the chairman of the Joint Chiefs of Staff, General Martin Dempsey.

The United States has been pushing Pakistan to launch a military offensive against militants in the North Waziristan tribal region, the reported base of the militant Haqqani network. The al-Qaida-linked group has attacked U.S. and NATO forces in Afghanistan.

Pakistan's army chief said Tuesday the U.S. should focus instead on stabilizing Afghanistan, and that Pakistan could take action in North Waziristan “tomorrow” if he were convinced it would solve all problems. General Ashfaq Kayani added that any such offensive would be Pakistan's decision.

Relations between the U.S. and Pakistan have been strained since the May 2 raid that killed al-Qaida leader Osama Bin Laden in the Pakistani city Abbottabad. Pakistan was not informed about the U.S. special forces operation in advance and condemned the raid as a violation of its sovereignty.

Pakistan has also rejected U.S. allegations that its military spy agency, the ISI, provides support to the Haqqani network.

Last month, then-U.S. military chief Admiral Mike Mullen accused the ISI of helping the Haqqani network launch attacks in Afghanistan, including an assault on the U.S. Embassy in Kabul.