Current Affairs - International - Discussion

Russia has rejected an Iranian request to buy S-400 missile defense systems, concerned that the sale would stoke more tension in the Middle East. The request was rebuffed by President Vladimir Putin on condition of anonymity because they're not authorized to discuss the matter. Iranian Foreign Minister Mohammad Javad Zarif visited Moscow May 7. Russia's Foreign Ministry didn't reply to a request for comment, and Iranian officials couldn't be reached for a response.