The agreement is set to be announced at the trilateral summit between the leaders of Japan, the U.S., and South Korea on Aug. 18.
The cooperation is aimed at strengthening the capabilities of both countries to counter potential threats and will represent the second joint missile development between Japan and the United States, following the completion of the Standard Missile-3 Block 2A in 2017, Yomiuri reported.
Prime Minister Fumio Kishida and U.S. President Joe Biden are expected to hold separate talks before the summit, which could affect the details of the deal’s announcement.
Hypersonic missiles are capable of reaching speeds five times higher than the speed of sound (Mach 5), and follow irregular trajectories at low altitudes, making it difficult to detect and track with existing radars.
To successfully intercept hypersonic missiles, it is important to have the ability to detect and track missiles at an early stage, Yomiuri stated. This is confirmed by practical experience in Ukraine, where Russian hypersonic missiles have been successfully intercepted by the Patriot missile system.
The US currently employs a “satellite cluster,” which includes many small satellites operating in a swarm, to intercept missiles. Japan is also exploring cooperation opportunities with the U.S. satellite network.
In addition, Japan seeks to have a “counterattack capability,” which would allow it to attack missile bases in other countries for self-defense. This includes the development of new missiles for interception and subsequent counterattacks. This system has received approval from Ukrainian defense experts.