Australia and Japan Sign Contract for First Upgraded Mogami-class Frigates

The Australian and Japanese governments have signed a contract for the first three upgraded Mogami-class frigates for the Royal Australian Navy. The ships are the initial phase of a larger program to acquire up to 11 new general-purpose frigates.

Contract Signing and Program Details

On April 18, 2026, officials from Australia and Japan signed the contract during a ceremony in Melbourne held aboard the Japanese Mogami-class frigate JS Kumano. The contract was signed with the Japanese government and Mitsubishi Heavy Industries (MHI).

This acquisition is the first step of Australia's SEA 3000 program. The program aims to replace the Royal Australian Navy's Anzac-class frigates. MHI was selected for the contract in August 2023.

Construction and Delivery Timeline

The first three frigates will be constructed in Japan. The first ship is scheduled for delivery in December 2029, with entry into service expected in 2030.

Construction of the subsequent eight frigates is planned to shift to the Henderson shipyard in Perth, Western Australia, pending the consolidation of the Henderson Defence Precinct. Austal is designated to build the Australian-constructed vessels.

Ship Specifications

The Australian variant is an evolved design of the Japanese Mogami-class, which MHI rebranded as "Upgraded Mogami" in 2024.

Key specifications include:

• A range of up to 10,000 nautical miles.
• A 32-cell Vertical Launch System.
• Armament including the ESSM Blk 2 surface-to-air missile, the NSM anti-ship missile, and Mk 54 lightweight torpedoes.
• A crew complement of 92 personnel.
• The ability to operate an MH-60R Seahawk helicopter.

This variant differs from the original Japanese Mogami-class by having twice the missile armament and a revised radar suite.

Financial Information

The Australian government's 2026 Integrated Investment Program committed up to $20 billion over the decade for general purpose frigates. The government has not disclosed the exact value of the contracts for the first three ships, citing commercial confidentiality.

In 2024, the total cost for the 11-frigate program was estimated at approximately $10 billion over a decade. The government states the higher $20 billion figure includes costs for redeveloping the Henderson shipyard and related infrastructure, and reflects a different timeframe.

Official Statements and Strategic Context

At the signing ceremony, Australian Deputy Prime Minister and Defence Minister Richard Marles stated the frigates would help secure maritime trade routes and northern approaches.

He described the goal as creating a "seamless" defence industrial base with Japan, citing strategic alignment and trust.

Japanese Minister of Defense Koizumi Shinjirō described the program as a major step to elevate the defence relationship between the two countries. He stated the focus is on increasing deterrence capabilities to avoid conflict.

The acquisition follows a 2024 independent analysis of the Navy's surface combatant fleet, which recommended more than doubling its size. Australian Defence Industry Minister Pat Conroy described the frigate acquisition as the fastest peacetime acquisition for the Royal Australian Navy.

Broader Regional Context

The agreement occurs as Japan has been relaxing restrictions on defence exports and adjusting its post-war pacifist stance. According to Source 2, China has criticized Japan's strategic shifts, expressing concern they could undermine regional stability.

Minister Koizumi stated that regional countries view Japan's posture positively.