Saudi Arabia’s King Salman has reportedly threatened Qatar with military action if the tiny Gulf country installs a Russian air defense system. “The kingdom would be ready to take all necessary measures to eliminate this defense system, including military action,” France’s Le Monde newspaper quoted the Saudi king as saying in a letter to the French government. In the letter, Salman reportedly said the Russian missiles would pose a security threat to the kingdom and asked for assistance from French President Emmanuel Macron in blocking the sale. Qatar’s ambassador to Russia had spoken publicly about talks to purchase a Russian S-400 missile air defense systems earlier this year, and the two nations signed an agreement on military and technical cooperation last year. Saudi Arabia joined Egypt, Bahrain, and the United Arab Emirates in severing ties with Qatar last year over accusations Doha sponsors terrorism.