The Trump administration approved a $133 million missile defense sale to Japan Tuesday to combat the escalating nuclear threat from North Korea.

The State Department says Congress was notified Tuesday of the proposed sale of four Standard Missile-3 (SM-3) Block IIA missiles, four MK 29 missile canisters, and other technical, engineering, and logistics support services.

The system was jointly developed by Japan and the U.S. in 2011 and can be employed on Aegis-class destroyers or on land, via the Aegis Ashore program, according to a State Department official.

The sale would follow through on President Donald Trump’s commitment for U.S. allies to purchase more American military equipment.

Throughout 2017, North Korea conducted a series of ballistic missile tests. Their most successful test came November 29, when Pyongyang said it launched a new type of intercontinental ballistic missile, topped with a “super-large heavy warhead,” one capable of striking the United States.