US, Australia, Japan slam Russia on Crimea

The United States, Japan and Australia have jointly criticised Russia's annexation of Crimea and its actions to destabilise eastern Ukraine.

The criticism was made in a statement following a trilateral meeting involving Barack Obama, Tony Abbott and Shinzo Abe on the sidelines of the G20 summit in Brisbane.

They also called for those responsible for the downing of flight MH17 over the Ukraine to be brought to justice.

"They resolved to tackle pressing issues such as ... opposing Russia's purported annexation of Crimea and its actions to destabilise eastern Ukraine, and bringing to justice those responsible for the downing of flight MH17," according to a statement.

The trio also recommitted to degrading and ultimately defeating the threat of Islamic State extremists and countering the threat posed by foreign terrorist fighters, as well as tackling Ebola.

The leaders also discussed eliminating the North Korean nuclear and missile threat and its addressing human rights issues.

There was also talk about the peaceful resolution of maritime disputes in Asian waters.

"The leaders expressed their firm commitment to deepen the already strong security and defence cooperation among the three countries and to strengthen the collective ability to address global concerns and promote regional stability," the statement said.

US, Australia and Japan will hold trilateral military exercises in Australia and work more closely on maritime security.

Cooperation will also be expanded in the areas of humanitarian assistance and disaster relief and tackling cyber warfare.

Australia's intent to replace the Collins Class submarine fleet is also understood to have been discussed.

Japan is considered a potential supplier of the submarines, although no final decision has been made.