The US government has approved the sale to Saudi Arabia of the advanced Terminal High Altitude Area Defense (THAAD) missile defense system for $15 billion, the State Department said Friday. "This sale furthers US national security and foreign policy interests, and supports the long-term security of Saudi Arabia and the Gulf region in the face of Iranian and other regional threats," a statement said. The sale “will support the foreign policy and national security objectives of the United States by improving the security of a friendly country,” the Pentagons Defense Security Cooperation agency said in a separate statement. Lockheed Martin and Raytheon will be the main US contractors in the sale of the THAAD system. The THAAD is one of the most capable defensive missile batteries in the US arsenal. Saudi Arabia will become among the first US allies to receive this important missile defense system.