Iran's supreme leader on Thursday criticized Arab and Muslim silence over the U.S. attack on Fallujah (search), and he urged the region's governments to help the Iraqi people.

"How can Muslim and Arabic governments accept playing the role of an indifferent observer? We can hear the voice of the needy coming from Iraqi families. Doesn't this voice deserve a protest by governments and the people against the arrogant Western powers?" Ayatollah Ali Khamenei (search) was quoted as saying by state-run Tehran radio.

U.S. troops led a major assault on Fallujah last week, seizing the city from insurgents suspected of using it as a base for carrying out bombings and kidnappings.

Khamenei said the silence over the offensive would encourage the Americans to carry out similar operations in other parts of Iraq.

"Killing thousands of civilians, executing the injured, arresting the innocent and destroying houses and mosques in Fallujah makes the eyes and hearts restless," he said.

American estimates of the number of insurgents killed in the offensive range from about 1,000 to about 1,200.

Tehran approved the toppling of Saddam Hussein (search), who fought a 1980-88 war with Iran, but it has opposed the U.S.-led occupation of Iraq, fearing U.S. troops on its doorstep will pose a security threat.

Washington has accused Tehran of interfering in Iraq and sending money and infiltrators to foment the insurgency there. Iran has denied the charges but said it didn't rule out the possibility that some infiltrators might have crossed its border illegally.