ISLAMABAD (Reuters) - U.S. military action against insurgents inwould be unacceptable and the country's army would be capable of responding, intelligence chief Ahmed Shuja Pasha told a meeting of political leaders in Islamabad, according to media reports.
Express News TV cited Pasha as saying an "American attack on Pakistan in the name of (fighting) extremism is not acceptable."
However, several television news reports said Pasha had also told an all-party meeting to discuss the crisis in ties between Washington and Islamabad that Pakistan would not allow the situation to get to a "point of no return."
Pakistan has long faced U.S. demands to attack militants on its side of the border with Afghanistan.
But the pressure has escalated since the top U.S. military officer, Admiral Mike Mullen, accused Pakistan last week of supporting an attack by the militant Haqqani network on the U.S. embassy in Kabul.
Support is growing in the U.S. Congress for expanding American military action in Pakistan beyond drone strikes against militants, said Senator Lindsey Graham, an influential Republican voice on foreign policy and military affairs.
Islamabad is reluctant to go after the Haqqanis -- even though the United States provides billions of dollars in aid -- saying its troops are stretched fighting Taliban insurgents.
Pakistan says it has sacrificed more lives than any of the countries that joined the "war on terror" after the September 11 attacks by Islamist militants on the United States in 2001.
Pakistan's military faced withering public criticism after a surprise U.S. raid that killed al Qaeda leader Osama bin Laden in a garrison town not far from Islamabad in May.
A similar U.S. operation against militants in North Waziristan on the Afghan border, where American officials say the Haqqanis are based, would be another humiliation for the powerful army.
Graham said in an interview with Reuters that U.S. lawmakers might support military options beyond drone strikes that have been going on for years inside Pakistani territory.
Those options may include using U.S. bomber planes within Pakistan, said, adding that he did not advocate sending U.S. ground troops into the country.
"I would say when it comes to defending American troops, you don't want to limit yourself," Graham said. "This is not a boots-on-the-ground engagement -- I'm not talking about that, but we have a lot of assets beyond drones."
Graham said U.S. lawmakers would think about stepping up the military pressure. "If people believe it's gotten to the point that is the only way really to protect our interests, I think there would be a lot of support," he said.
Pakistan was designated a major non-Nato ally by the United States for its support of coalition military operations in Afghanistan after 9/11.
But their relationship has been dogged by mistrust. Although
regarded as critical to U.S. efforts to stabilize Afghanistan, Pakistan is often seen from Washington as an unreliable partner.
Following U.S. accusations that some in the Pakistani government have aided anti-U.S. militants, Congress is re-evaluating its 2009 promise to triple non-military aid to Pakistan to a total of $7.5 billion over five years.
That aid came on top of billions in security assistance provided since 2001, which Washington is also rethinking.
Any unilateral U.S. military action to go after the Haqqanis would deepen anti-American sentiment in Pakistan, which is already running high over U.S. drone strikes and other issues, reducing the space for the government and army to collaborate with Washington.
The Haqqani network is allied with Afghanistan's Taliban and is believed to have close links to al Qaeda. It fights U.S. and NATO forces in eastern Afghanistan. The group's leader says it is no longer based in North Waziristan and feels secure operating in Afghanistan after making battlefield gains.
(Additional reporting by Zeeshan Haider and Augustine Anthony in Islamabad, Mirwais Harooni in Kabul and Missy Ryan and Susan Cornwall in Washington; Writing by Michael Georgy; Editing by John Chalmers)