WASHINGTON Oct 6 (Reuters) - The U.S. State Department has approved the possible sale of a THAAD anti-missile defense system to Saudi Arabia at an estimated cost of $15 billion, the Pentagon said on Friday.


The proposed sale "will support the foreign policy and national security objectives of the United States by improving the security of a friendly country" and will not alter the basic military balance in the region, the Pentagon's Defense Security Cooperation agency said in a statement.

Lockheed Martin Co and Raytheon Co are the principal contractors for THAAD or Terminal High Altitude Area Defense. (Reporting by Mohammad Zargham; Editing by Eric Walsh)