Japan will start procuring Tomahawk cruise missiles from the United States in fiscal 2025, a year earlier than initially planned, in response to the worsening Asian security environment, Defense Minister Minoru Kihara said Wednesday.

Kihara, who took up his new post in a Cabinet reshuffle in mid-September, made the announcement when he met the press in Washington after holding his first face-to-face talks with his U.S. counterpart Lloyd Austin.

Amid growing security challenges presented by China, North Korea and Russia, Kihara and Austin confirmed their mutual interest in ramping up the Japan-U.S. alliance's deterrence and response capabilities while modernizing the partners' roles and missions, officials said.

As part of preparations to acquire "counterstrike" capabilities, or the ability to hit enemy bases should the need arise, Japan plans to purchase 400 Tomahawks, which have a strike range of about 1,600 kilometers.

Japanese Defense Minister Minoru Kihara (front L) holds talks with U.S. Defense Secretary Lloyd Austin (3rd from R) at the Pentagon on Oct. 4, 2023. (Kyodo) 

The defense chiefs "shared the recognition" that the procurement of Tomahawk Block-4 missiles will begin in the fiscal year starting in April 2025, a Japanese official said, noting that the purchase still needs to be approved by the U.S. Congress, with both sides, for this reason, refraining from calling it formally "agreed."

Originally, Japan was planning to buy the latest Tomahawk Block-5 missiles in fiscal 2026 and 2027 to deploy them on Maritime Self-Defense Force Aegis destroyers.

Now, of the 400 U.S.-made missiles, it plans to buy up to 200 of the previous version between fiscal 2025 and fiscal 2027, according to the official. The rest of the purchase will be made up of newer missiles that are expected to be delivered to Japan as per the original schedule.

While speaking to reporters, Kihara said he has determined that changing the schedule will "contribute to the drastic strengthening of our country's defense capabilities sooner."

He said the capabilities of the two versions, such as their strike ranges, are more or less the same and the launching system for them is also compatible.

For the purchase, the Japanese government has earmarked 211.3 billion yen ($1.4 billion) in the budget for fiscal 2023 that started in April. As around half the missiles being purchased are an older version, the change will likely reduce the cost of the procurement.

Tomahawks, first used in the 1991 Gulf War, can cover Chinese coastal areas and are deemed essential by Japanese officials to beef up Tokyo's defense capabilities until it can introduce domestically made cruise missiles.

"This is a time of historic momentum in the U.S.-Japan alliance," Austin said as he welcomed Kihara to the Pentagon.

Austin said he wants to work closely with Kihara to make the alliance even stronger in response to China's "coercive behavior, North Korea's dangerous provocations and Russia's war of choice against Ukraine."

During the meeting that lasted almost an hour, the defense chiefs discussed priorities for Japanese and U.S. forces in the years to come, including how best to maintain an open, free, and rules-based Indo-Pacific, according to the officials.

Kihara told Austin Japan and the United States need to "strengthen the alliance's capabilities to deter and respond" to any attempts to change the status quo by force as that cannot be tolerated anywhere in the world.

In light of China's increased military activities and its deepening cooperation with Russia, the two agreed to boost cooperation "more than ever" and reaffirmed the importance of peace and stability across the Taiwan Strait, according to Japan's Defense Ministry.

Late last year, in a major policy shift under Japan's war-renouncing Constitution, the Cabinet of Prime Minister Fumio Kishida approved plans to significantly bolster the country's defense and sharply increase spending toward that end.

The United States has welcomed the development, including its acquisition of counterstrike capabilities.

Kihara, who was a special national security adviser to former Japanese prime ministers Shinzo Abe and Yoshihide Suga, arrived in the U.S. capital on Tuesday for a three-day visit.

Kihara said he separately met with U.S. President Joe Biden's top national security aide Jake Sullivan on Wednesday.

Also high on the agenda for the meeting between Kihara and Austin was the enhancement of trilateral cooperation with South Korea to deal with North Korea's missile and nuclear threat, as well as supporting Ukraine as it battles Russia's invasion, now in its 20th month, according to the officials.

Citing a summit Biden hosted at his Camp David retreat in mid-August with the leaders of Japan and South Korea, Austin said the three countries' forces should forge closer ties through new initiatives such as sharing real-time missile warning data and conducting joint exercises.