This marks the first time these four countries have carried out maritime exercises together in the South China Sea.
Multinational engagements of this kind are conducted to maintain stability and peace in the region, while strengthening cooperation with partner nations.
Both vessels commenced their regional deployment on 5 October. It was fourth such deployment for HMAS Hobart and Arunta this year.
In support of the two vessels, the US Navy deployed its Arleigh Burke-class destroyers USS Milius (DDG 69) and USS Higgins (DDG 76).
USS Milius commanding officer commander Matthew Hays said: “Working with our Australian, Canadian and Japanese allies in the South China Sea has been an invaluable experience and opportunity.
“Combined maritime exercises help us strengthen interoperability and increase collective war-fighting readiness.
“It was great to be able to work with these three navies and to demonstrate our unwavering strong support for their increasing role in the region and our commitment to a free and open Indo-pacific.”
During this period, the US Navy, the RAN, the RCN and JMSDF conducted several complex maritime missions and training drills in the Indo-Pacific region.
The integrated operations included air, surface and sub-surface defence exercises involving naval vessels and maritime patrol aircraft.