A film on the life of the prophet Muhammad is expected to break box office records in Shi'ite Muslim Iran after its release on Thursday, but some Sunni Muslim clerics in the Arab world are already demanding that Tehran ban it.The state-sponsored Mohammad, Messenger of God, directed by Oscar-nominated director Majid Majidi, is at $40 million Iran's most expensive movie to date."I decided to make this film to fight against the new wave of Islamophobia in the West. The Western interpretation of Islam is full of violence and terrorism," Majidi was quoted as saying by Hezbollah Line, a conservative Iranian magazine.The 171-minute movie, the first part of a planned trilogy, focuses on the prophet's childhood. His face will not be shown on screen, in accordance with traditional Islamic strictures. The camera shows the boy actor playing him only from behind, or only his shadow.A steadicam was customized especially to depict Mohammad's point of view by the movie's Oscar-winning Italian cinematographer Vittorio Storaro. The identity of the boy playing Mohammad has not been made public.Egypt's Al-Azhar, the most prestigious institute of Sunni Islam, is not satisfied with such precautions and has called on Iran to ban the film."This matter is already settled. Sharia (Islamic law) prohibits embodying the prophets," Al-Azhar told Reuters in a statement."It is not permissible in Islam that someone (an actor) has contradictory and conflicting roles; sometimes we see him as a blind drunk, sometimes as a womanizer ... and then he embodies a prophet ... this is not permissible."Regional rivalry between Sunni power Saudi Arabia and Shi'ite Iran has intensified mutual suspicion between followers of the two branches of Islam in recent decades. There has been no official comment on the movie yet from Saudi Arabia, where Islam was born more than 1,400 years ago."Most of these reactions are political," Sami Yusuf, who is one of the Islamic world's biggest musical stars and who sang the soundtrack for the film, told Reuters."I am sure people in Al-Azhar and others who criticize the film haven't seen it yet. They are against the film only because it's a cultural export of Iran."He said it was a "shame" there were only two major productions describing the life of Muhammad, in contrast to the many on Jesus Christ and other prophets.Depictions of Muhammad have often provoked angry unrest after being deemed blasphemous by Muslims. Cartoons published by a Danish newspaper in 2005 were followed by violent protests in which scores of people died, attacks on embassies and consumer boycotts.Islamist militants shot dead 12 people at the offices of French magazine Charlie Hebdo in January this year, saying they were avenging its blasphemous cartoon depictions of Mohammad.Iran's late Supreme Leader issued a fatwa calling on Muslims to kill writer Salman Rushdie in 1988 for The Satanic Verses, a novel deemed blasphemous in its treatment of Muhammad and Islam.Muhammad, Messenger of God is only the second full-length movie drama on the prophet. The first, The Message (1976), was directed by Syrian Moustapha al-Akkad. Anthony Quinn played Muhammad's uncle, Hamza.That film did not depict Muhammad's face on screen, but some Muslims were offended. Akkad was killed in a 2005 suicide bombing in Amman. It is not known whether the attack was related to the movie."You cannot study Mohammad's life and not fall in love with him and his character. If this film makes people of the world know our prophet better and see how kind he was, we have done our job," singer Yusuf said.Muhammad, Messenger of God has been mainly shot in Iran. Mecca was recreated on a large scale and in minute detail. Scenes with elephants were filmed in South Africa, after India refused to let the filmmakers in, fearing the reaction of Muslim countries to the movie.Iran's Supreme Leader, Ayatollah Ali Khamenei, has visited the film set through the production, in a strong sign of support.The film is being released in 143 cinemas in Iran on the same day as it opens at the Montreal Film Festival.One cinema in Tehran, which asked not to be named for legal reasons, said the movie was their most popular at the moment.