Japan’s prime minister issued a warning Monday about an impending North Korean satellite launch, after the Japanese coast guard reportedly announced Pyongyang plans to launch a satellite into waters near the Korean Peninsula as early as May 31.

Fumio Kishida pledged to work with the U.S. and South Korea to call on North Korea to exercise “restraint” and desist from launching a “ballistic missile” under the guise of a satellite launch, according to a cabinet office press release.