Australia and the United States on Tuesday signed an agreement that will see them jointly develop and test hypersonic cruise missiles capable of destroying warships of the People's Liberation Army Navy (PLAN) at very long range.

The government of prime minister Scott Morrison has earmarked US$6.8 billion (A$9.3 billion) to develop high-speed, long-range missile defense systems, including hypersonic cruise missiles, in a bid to pull ahead of China in hypersonics. The spending is part of the government's 2020 force structure plan.

Both countries will partner to develop an air-launched hypersonic cruise missile under the bilateral Southern Cross Integrated Flight Research Experiment program, or SCIFiRE. The program will be executed by the U.S. Air Force under the auspices of the weapons program executive officer.

SCIFIRE will leverage the collaborative work undertaken in partnership with the Royal Australian Air Force (RAAF), the Australian Defense Science and Technology Group, and the University of Queensland on the Hypersonic International Flight Research Experimentation program.

Australian Defense Minister Linda Reynolds said the collaboration with the U.S. will culminate in flight tests of a hypersonic missile capable of reaching a speed exceeding Mach 5 (6,000 km/h) to see how the weapon performs in operational conditions.

"Developing this game-changing capability with the United States from an early stage is providing opportunities for Australian industry," said Reynolds.

"This demonstrates the Morrison government's commitment to strengthening Australia's sovereign defense industry while creating more high-tech Australian jobs and enhancing the ADF's self-reliance."

Reynolds also said investing in capabilities that deter actions against Australia "also benefits our region, our allies and our security partners."

In July, the Morrison government announced a boost to defense spending by 40% over the next 10 years in order to acquire longer-range aerial, naval and amphibious strike capabilities.

The hypersonic missile under joint development will deploy a conventional high-explosive warhead to a target hundreds of kilometers away. It will be able to fly the 710 km distance between Sydney and Melbourne in only seven minutes. In contrast, a passenger plane takes more than an hour to cover the same length.

The move to massively boost Australia's offensive capabilities comes as it's broadened its military focus from the Pacific Ocean to the far larger Indo-Pacific region extending out to the Indian Ocean.

Collaborating on hypersonics is nothing new for Australia and the U.S. Both have worked together for 15 years on research into hypersonic scramjets, rocket motors and sensors.

The new missile will be a Mach 5-class precision strike missile that is propulsion-launched and powered by an air-breathing scramjet engine. It's expected to enter service within the next five to 10 years. Testing will take place in Australia.

"SCIFiRE is a true testament to the enduring friendship and strong partnership between the United States and Australia," said Michael Kratsios, acting undersecretary of defense for research and engineering.

"This initiative will be essential to the future of hypersonic research and development, ensuring the US and our allies lead the world in the advancement of this transformational warfighting capability. We thank the Australian Department of Defense for their shared commitment to this game-changing effort."