TOKYO: Japan and the United States plan to jointly develop a new missile to intercept hypersonic weapons, which are being developed by China, North Korea and Russia, it was learned Monday.

Japanese Prime Minister KISHIDA Fumio and US President Joe Biden are expected to reach an agreement on the joint development at their bilateral meeting on the sidelines of a trilateral summit among the two countries and South Korea on Friday.

It will be the second time for Tokyo and Washington to jointly develop an interceptor missile, after the Standard Missile-3 Block 2A missile.

Japan’s existing missile defense system is a two-part regime in which the SM-3 missile is launched from an Aegis destroyer of the Maritime Self-Defense Force to intercept threats outside the atmosphere, and the Ground SDF’s Patriot Advanced Capability-3, or PAC-3, surface-to-air missile is used when threats are falling.

Hypersonic weapons travel at more than five times the speed of sound at relatively low altitudes and with irregular trajectories, making them harder to intercept than conventional ballistic missiles with parabolic trajectories.

Japan and the United States agreed to start a joint study on how to respond to such weapons at a so-called two-plus-two meeting among their foreign and defense ministers last year.

For now, Japan’s Defense Ministry plans to deal with hypersonic weapons by using Standard Missile-6 missiles on MSDF Aegis destroyers and an improved version of the Type 03 medium-range surface-to-air guided missile of the GSDF.

Both missiles, however, are primarily designed to intercept falling threats. The new missile to be jointly developed is expected to intercept threats at an earlier stage.

As hypersonic weapons fly at low altitudes, there could be delays in detecting them with ground-based warning and control radars, so the Japanese government is rushing to establish a network of many small satellites to monitor threats constantly.

The government is also seeking to acquire US-made Tomahawk cruise missiles, as part of its effort to gain counterstrike capabilities.

JIJI Press