Pakistan's Foreign Minister Hina Rabbani Khar said the United States could ill afford to jeopardize its relationship with Pakistan, and that doing so “will be at their own cost.” (MARK RALSTON/AFP/GETTY IMAGES)

Pakistan’s powerful army chief on Friday rejected the top U.S. military commander’s allegation that Pakistan’s prime spy agency aided a deadly insurgent attack on the U.S. Embassy in Kabul, saying that the claim was “disturbing” and “not based on facts.”

In a brief statement, Gen. Ashfaq Parvez Kayani said the charges about his intelligence agency’s ties to the Haqqani militant network were baseless and part of a “blame game in public statements” — a reference to increasingly pointed comments by American officials about links between the Haqqanis and Pakistan, a U.S. ally.

Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, told a Senate committee Thursday that the Pakistani military’s Inter-Services Intelligence agency, or ISI, had provided support for several assaults on U.S. targets carried out by the network, an Afghan guerilla group based in Pakistan’s border region. He referred to the militant organization as a “veritable arm” of the ISI.

Kayani denied what he called “accusations of proxy war and ISI support to Haqqanis,” and he seemed to suggest that the United States — which is trying to encourage reconciliation talks to end the U.S.-led Afghan war — has its own lines of communication with the militant group.

“Admiral Mullen knows fully well which . . . countries are in contact with the Haqqanis,” Kayani’s statement said. “Singling out Pakistan is neither fair nor productive.”

U.S. officials have long said privately that Pakistani intelligence aids the Haqqani network. But Mullen’s comments were the most serious and specific yet, and they followed recent warnings by other U.S. officials that the United States would resort to unilateral action against the Haqqanis if Pakistan did not take them on. Kayani’s statement gave no indication that the Pakistani army, which has received billions of dollars in U.S. aid over the past decade, plans to do so.

The army chief’s response came after similarly sharp dismissals from Pakistani government officials, who have ceded most control over security issues and the U.S. relationship to the military. Speaking to a Pakistani television network, Foreign Minister Hina Rabbani Khar said that the United States could ill afford to jeopardize its relationship with Pakistan and that doing so “will be at their own cost.”

“Anything which is said about an ally, about a partner publicly to recriminate it, to humiliate it is not acceptable,” Khar said.

A senior State Department official said Friday that the country had a “vital interest” in continuing to work with Pakistan to fight terrorism. “These are problems that threaten both of us. We have had some counterterrorism successes. We need to continue to fight this battle together, and we will,” said the official, who asked not to be identified to discuss sensitive issues.

Pakistani Prime Minister Yousaf Raza Gillani told reporters in Pakistan’s largest city, Karachi, that the United States was ignoring the “feelings” of Pakistanis, who want “to defend their motherland and its sovereignty.” The United States, he said, “cannot live with us and cannot live without us.”

In the middle of the sharp exchanges between officials of the two countries, the head of the U.S. Central Command arrived in the Pakistani capital late Friday and was scheduled to meet with Kayani, the Associated Press reported Saturday, citing a U.S. Embassy spokesman in Islamabad.

Pakistan has long maintained that its links to the Haqqani network are minimal and do not extend to support, and the military has said its troops are too overstretched fighting domestic insurgents to challenge the Haqqanis in their refuge of North Waziristan. Some U.S. officials acknowledge that the Pakistani army could not defeat them in a traditional offensive, but U.S. officials say Pakistan could take other measures against the network.

As pressure from Washington has ratcheted up this week, Pakistani officials have accused the United States of trying to transfer blame for its faltering war in Afghanistan. Pakistani military officials say that the Haqqanis are now based in eastern Afghanistan and that NATO forces are also at fault for not halting fighters before they arrive in Kabul to carry out attacks.

“If the U.S. is so sure about the Haqqanis’ long-distance travel to Kabul, why don’t they use drone strikes against them,” as they do in North Waziristan, said one senior military officer, who asked for anonymity because he is not authorized to speak publicly. “The problem lies in Afghanistan.”

Khar, speaking to an Indian television network, echoed a claim regularly made by the Pakistani military, saying the United States had not shared evidence about ISI collusion with the Haqqanis. U.S. officials strongly dismiss that, saying they have often laid out the evidence, including to ISI chief Ahmad Shuja Pasha when he visited Washington on Tuesday.

A Pakistani intelligence officer denied Friday that the ISI backed the Haqqanis. As proof, he said the son-in-law of a former member of Pakistan’s joint chiefs of staff was kidnapped and is being held in North Waziristan by militants under the Haqqanis’ sway. Kayani, the army chief, has been unable to secure his release, the intelligence officer said, asking, “Where is our control on the group?”

In his testimony, Mullen said Pakistan used the Haqqanis as “proxies” in a likely attempt at “redressing what they feel is an imbalance in regional power.” The comment was a reference to Pakistan’s anxiety about archfoe India, whose sway is increasing in Afghanistan.

In a column in the Pakistani English-language daily newspaper Dawn, analyst Khalid Aziz said this posture is unlikely to change as the United States draws down in Afghanistan.

“India could begin to have greater influence in Afghanistan after U.S. withdrawal,” Aziz wrote. “Thus the play of India-Pakistan rivalry in Afghanistan reduces Pakistan to treat the Haqqanis as a strategic asset.”

Kayani said Pakistan is “fully committed” to peace in Afghanistan.

Special correspondent Haq Nawaz Khan contributed to this report from Peshawar.