Under the deal announced last year and billed as one of Japan’s biggest defence export deals since World War II, Australia will pay A$10 billion (US$6 billion) over the next 10 years to acquire the fleet of stealth frigates.

Japan’s defence minister Koizumi Shinjiro attended the signing of the contract to deliver the first three of the ships, Australia’s defence ministry said.

“This is the fastest acquisition for the Royal Australian Navy in peacetime,” Australia’s minister for defence industry Pat Conroy said.

“We are working closely with Japanese and Australian industry partners as we acquire one of the most, if not the most, advanced general-purpose frigates in the world,” he added.

Australia is striving to expand its fleet of major warships from 11 to 26 over the next decade.

Mitsubishi Heavy Industries was awarded the tender over Germany’s Thyssenkrupp Marine Systems.

Mogami-class warships are advanced stealth frigates equipped with a potent array of weapons.

Japan is deepening cooperation with US allies in the Asia-Pacific region that, like Tokyo, are involved in territorial disputes with China.

Both Japan and Australia are members of the “Quad” group alongside India and the US.