The United States, Britain and Australia have agreed to work together to develop “advanced hypersonic and counter-hypersonic” weapons under their AUKUS trilateral security pact as China and Russia continue to make leaps in their own hypersonic programs.

The move, announced Tuesday, also left the door open for other partner countries such as Japan to work with AUKUS nations on the issue in the future in the wake of Russia’s invasion of Ukraine. The bloody war there has triggered concern in Asia over the region’s own increasingly severe security environment.

Much of the early focus on the AUKUS alliance — formed last September and widely seen as a trilateral attempt at countering China’s increasingly potent military power in the region and beyond — had been on nuclear submarines.