The U.S. agreed Tuesday to sell two Aegis Ashore missile defense systems and other military equipment to Japan at an estimated cost of $2.15 billion, or about ¥235 billion.

But in Yamaguchi and Akita prefectures, where the Aegis Ashore systems will likely be deployed, concerns over environmental damage and their proximity to populated areas could make their planned deployment in fiscal 2023 challenging.

It was announced that the U.S. State Department had approved the sale in a statement posted by the U.S. Defense Security Cooperation Agency. The agency the same day notified the U.S. Congress, which is expected to formally approve the sale.