Pakistan, enraged by a NATO cross-border attack that killed 24 soldiers, could end support for the U.S.-led war on militancy if its sovereignty is violated again, the foreign minister said, warning “enough is enough.”

A senior Pakistani army official has said a NATO cross-border air attack that killed 24 soldiers was a deliberate, blatant act of aggression, hardening Pakistan's stance on an incident that could hurt efforts to stabilize Afghanistan.

Thousands gathered outside the American consulate in the city of Karachi on Sunday to protest against a NATO cross-border air attack that killed 24 Pakistani troops and is threatening a strategic alliance between the countries.

Pakistan on Saturday accused NATO helicopters and fighter jets of firing on two army checkpoints in the country's northwest, killing 24 soldiers. Islamabad retaliated by closing the border crossings used by the international coalition to supply its troops in neighboring Afghanistan.

The Pakistani and Chinese attack choppers swoop low across the valley, strafing a mock terrorist hideout and a bomb-making factory. Then a joint commando team storms the camp -- to the gentle applause of top brass from both nations watching from the stands.

Pakistan's most troubled foreign relationships have improved in recent months, its top diplomat said on Saturday, pointing to upcoming trade talks with New Delhi and broad agreement on regional security goals with Washington as evidence.

A U.S. drone strike on Thursday killed five commanders of a powerful Pakistani Taliban faction which attacks Western forces in Afghanistan, one of the group's leaders told Reuters.

U.S. Secretary of State Hillary Clinton delivered a tough warning to Pakistan on the eve of a visit to the country on Thursday, saying it was time for Islamabad to decide whether it would help or hinder the U.S.-led war on militants.

The United Nations appealed for US$357 million Sunday to help millions of Pakistanis affected by floods that have damaged hundreds of thousands of homes and destroyed millions of acres of crops.

Three Pakistani soldiers were killed and one Indian trooper was hurt in an exchange of fire by the rival militaries across their sensitive border in divided Kashmir, authorities said Thursday.