Japan's Defense Ministry has announced that the country's Maritime Self-Defense Force and the US and South Korean navies held a joint drill in the Sea of Japan.
Wednesday's drill follows North Korea's launch of an ICBM-class missile on Saturday and two short-range ballistic missiles on Monday.
Japan, the US and South Korea each sent a destroyer equipped with the Aegis missile-tracking system.
The three countries previously held a joint anti-missile drill in October. This time, they confirmed procedures for sharing information on the missiles launched.
Defense Ministry officials say the drill aims to promote cooperation among the three countries in an increasingly harsh security environment, and to showcase their involvement in strengthening the rules-based international order.