KABUL — Afghan President Hamid Karzai's government lashed out Saturday at his foreign critics, accusing a top U.N. official and other international figures of interfering in the country's internal affairs.

The Foreign Ministry took issue with U.N. Special Representative Kai Eide, who recently issued a list of reforms that he expected Karzai to make. Such comments "exceeded international norms" and "violated respect for Afghanistan's national sovereignty," the ministry said in a statement.

In an incident that could exacerbate tensions between Karzai's government and the West, international and Afghan forces were investigating Saturday whether a NATO airstrike in the northwest of the country killed eight Afghans and injured 22 people, including five U.S. troops. The casualties, most of them Afghan soldiers and policemen, occurred during a joint manhunt for two U.S. paratroopers missing since Wednesday.

At a news conference Thursday, Eide warned Karzai that he risked losing the support of international donors and troops unless he cleansed his government of corruption and warlords.

"We can't afford any longer a situation where warlords and power brokers play their own games," Eide said. "We have to have a political landscape here that draws the country in the same direction, which is in the direction of significant reform."

President Barack Obama and British Prime Minister Gordon Brown have made similarly pointed remarks since Karzai was declared the winner Monday of a drawn-out election tainted by fraud. Both leaders need a credible partner in Kabul to justify sending additional troops to fight an escalating Taliban insurgency.

"Over the last few days, some political and diplomatic circles and propaganda agencies of certain foreign countries have intervened in Afghanistan's internal affairs by issuing instructions concerning the composition of Afghan government organs and political policy of Afghanistan," the Foreign Ministry statement said.

It noted that Karzai has pledged to make the fight against corruption and other reforms a top priority of his next administration.

"Without doubt, consultation and discussion ... is essential," the statement said. "However, it is necessary to ensure respect for Afghanistan's national sovereignty."

Dan McNorton, a spokesman for the U.N. mission in Afghanistan, said its mandate was to "support and also to advise the government."

"Of course, some of that advice is going to be unpalatable," he said.