SaudiMac reports, that Apple has officially confirmed and outlined where their FaceTime video calling service isn't available. When looking at the chart, every country and carrier with a footmark of "4" doesn't support FaceTime. If you look through the entire support article you will find that five Middle Eastern countries, cropped out and shown below in the screenshot, are the only ones that don't support FaceTime, including: "Jordan, Qatar, Saudi Arabia, and the United Arab Emirates." Oh, and Apple is very clear to say "FaceTime isn't available on this CARRIER." -- Saying it's the carrier's decision?
Reference: KB HT1937