On Saturday April 18, Australia and Japan took a significant step in deepening their strategic defence partnership, by finalising contracts in Melbourne for the acquisition and construction of Mogami-class frigates under the SEA 3000 program.

The agreement was formalised by Deputy Prime Minister and Defence Minister Richard Marles, and Defense Minister for Japan Koizumi Shinjiro, marking a major milestone in Australia’s effort to modernise its surface fleet.

Speaking at the event, Mr Marles emphasised the importance of the agreement to Australia’s future naval capability.

“This agreement is absolutely fundamental for delivering capability for the Royal Australian Navy,” he said.

“We will see the first of these frigates delivered in December 2029, and in the early 2030s, the general purpose frigate, the Mogami-class, will be the backbone of continuous naval shipbuilding in Western Australia.”

The SEA 3000 program is a key pillar of the Australian Government’s broader naval expansion, aimed at enhancing maritime security and operational reach.

“Our surface fleet is more important than at any time in decades,” Mr Marles said.

“These general purpose frigates will help secure our maritime trade routes and northern approaches as part of a larger and more lethal surface combatant fleet.”

'This is the beginning of a long-term endeavour built on trust, shared purpose and a clear-eyed understanding of the strategic environment we face together.'

Mr Koizumi described the agreement as an historic moment for bilateral defence cooperation.

“Crossing the vast distance that spans the Pacific from north to south, this marks a ground-breaking start in connecting Japan and Australia's defence equipment, industries, technologies and above all, the many people involved,” Mr Koizumi said.

"I feel great pride in Japan's outstanding defence industry, and great joy to be able to deliver such equipment to the men and women of the Royal Australian Navy."

Chief of Navy Vice Admiral Mark Hammond and Chief of Staff of the Japan Maritime Self-Defense Force Admiral Saito Akira attended the ceremony.

Vice Admiral Hammond reflected on the enduring relationship between the two nations’ naval forces, drawing historical parallels including Australia and Japan’s close alliance in the Pacific during the First World War.

“In the First World War, it was the Japanese cruiser Ibuki that hauled up her battle ensign to join HMAS Sydney I in investigating an SOS from near the Cocos Keeling Islands,” Vice Admiral Hammond said.

“Ibuki was ordered back into formation to protect the thousands of soldiers aboard the troop ships, as Sydney sailed over the horizon to our Navy’s first victory at sea against the German ship Emden.

“On Anzac Day ... I will be reflecting on our sailors sailing side by side in those formative years of our nation and our Navy.”

The agreement signals not only a significant capability uplift for the Royal Australian Navy, but also a deepening of defence ties between Australia and Japan, with both nations committing to closer collaboration in an increasingly complex Indo-Pacific security environment.

"I look ahead to the years when our sailors will continue to sail side by side, where our soldiers and aviators will increasingly serve together," Vice Admiral Hammond said.

“This is the beginning of a long-term endeavour built on trust, shared purpose and a clear-eyed understanding of the strategic environment we face together.”