WASHINGTON — Boeing has been awarded a $3.2 billion contract from the U.S. Army to sell Apache helicopters to Saudi Arabia, according the Defense Department.

The contract modification calls for full-rate production of new and existing AH-64E Apache helicopters and will be overseen by the U.S. Army Contracting Command, Redstone Arsenal, Alabama.

The project will be carried out at Boeing’s Mesa, Arizona, facility, with an estimated completion date of June 30, 2022.

Defense News’ land warfare reporter, Jen Judson, reported in February that the Saudi Arabian National Guard was planning to build a rotary-wing force. It currently has 36 helicopters — up from having none less than two years ago — with an end goal of expanding to 156 aircraft.

The U.S. Army is helping to oversee the development of a rotary unit for SANG, including 42 Army aviators working to train and assist in modernization efforts.

“We are training everything across the board,” from maintainers to refuelers to firefighters, not just pilots, said U.S. Army Maj. Gen. Frank Muth, the Saudi Arabian National Guard modernization program manager.

The unit cost for a new Apache helicopter is $35.5 million — based on fiscal 2014 numbers — and $21.5 million for a unit rebuild, according to the Department of Defense fiscal 2016 budget request.

In addition to the U.S. Army and Saudi Arabia, the AH-64 Apache multi-role combat helicopter is operated by the militaries of Egypt, Greece, Israel, Japan, South Korea and the United Kingdom, according to UPI.

The Apache first came into service with the U.S. Army in the 1980s.