Defense Minister Yasukazu Hamada said Tuesday Japan plans to buy all the Tomahawk cruise missiles it is seeking from the United States in one go in fiscal 2023 rather than over several years as initially planned.

Hamada, speaking at a press conference, did not give a reason for the change of plan or say how many of the U.S.-developed long-range missiles the government would buy, saying only that it is eyeing procuring "all of the required quantity" in the year starting April.

Japan has been considering purchasing up to about 500 Tomahawks, according to a government source.

The move came as the government aims to enhance its deterrence through the acquisition of "counterstrike capabilities" as pledged in three key security documents revised in December amid China's military buildup and the North Korean missile and nuclear threats.

Handout released by the U.S. Navy shows a Tomahawk cruise missile launched from a U.S. Navy guided-missile destroyer in the Mediterranean Sea in March 2011. (U.S. Navy/Getty/Kyodo)

The documents said Tomahawk missiles, with a strike range of about 1,600 kilometers, covering Chinese coastal areas, would underpin the capabilities for striking targets in enemy territory in the event of emergencies until Japan deploys home-made missiles.

The source said earlier that Tokyo is also eyeing consultation with Washington to explore the possibility of moving forward the start of the cruise missiles' domestic deployment from the currently scheduled fiscal 2026.

A draft initial budget for fiscal 2023, decided by Prime Minister Fumio Kishida's Cabinet in December, said 211.3 billion yen ($1.6 billion) will be set aside for the procurement of Tomahawk missiles.

Tomahawks are known for their use in the 1991 Gulf War and the 2003 Iraq War.

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