WASHINGTON - The U.S. State Department has approved a $75 million deal for Raytheon to upgrade and maintain Phalanx Close-In Weapon Systems operated by Britain’s Royal Navy.

Congress was notified Wednesday of the deal, for 50 Block IB Baseline 2 Upgrade Kits of the MK 15 Phalanx CIWS, according to the Defense Security Cooperation Agency.

The kits would be used for close-in ship self-defense against air and surface threats onboard the UK's naval combatants and auxiliaries, according to the announcement.

The self-contained system includes search, detection, threat evaluation, tracking, engagement and kill assessment. Block 1B adds a forward-looking infrared sensor that can be used against helicopters and high-speed surface craft at sea while the land-based version helps identify and confirm incoming dangers, according to Raytheon.

Because of their distinctive barrel-shaped radome and their automated operation, Phalanx CIWS units are sometimes nicknamed “R2-D2” after the famous droid character from the Star Wars films.

Raytheon Missile Systems, of Tucson, Ariz., is the prime contractor. Its work would include program and technical reviews, plus training and maintenance support in-country as required.

“This proposed sale will support U.S. foreign policy and national security objectives of the United States by improving the security of a NATO ally which has been, and continues to be, an important partner on critical foreign policy and defense issues,” the announcement reads.