By UPI

TEHRAN, Sept. 13 (UPI) -- The Iranian government expressed frustration that Washington hadn't come out with a public criticism of a film seen as insulting to Islam.

Anti-American sentiment turned deadly this week in Libya after the U.S. Embassy in Benghazi was attacked, leaving several diplomats, including Ambassador Christopher Stevens, dead. Protests were reported at U.S. diplomatic outposts in Yemen, Egypt and elsewhere.

It was unclear exactly which protests were related to a low-budget film produced in the United States that was deemed offensive to the Islamic Prophet Mohammed. The attack in Benghazi, for instance, appeared to have been a planned assault rather than a protest that turned violent.

Iranian Foreign Ministry spokesman Ramin Mehmanparast expressed frustration that the U.S. government hadn't criticized the film.

"The Islamic Republic ... stresses that the systematic and continuous silence of the U.S. administration in case of such disgusting moves that are made in line with anti-Islam campaign is the main factor for the continuation of such moves," he was quoted by the semiofficial Fars News Agency as saying.

U.S. President Barack Obama, in a Wednesday statement on the attacks in Libya, said religious diversity was a guiding principle for the United States.

"We reject all efforts to denigrate the religious beliefs of others," he said. "But there is absolutely no justification to this type of senseless violence."

In a statement to CNN, actors and crew members involved in the film said they were "grossly misled" about its content.

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