A declassified review of the Australian Defence Force says the nation cannot rely on long warning times for a conflict given the ability for adversaries to strike rapidly from afar or through non-conventional means such as economic coercion.

China’s rapid military build-up, the decline of the United States as a unipolar power in the Indo-Pacific, nuclear war, climate change, workforce issues and the increase in grey zone attacks such as cyber attacks have all been identified as security threats.

Former defence minister Stephen Smith and ex-defence force chief Angus Houston, who led the independent review, said the new challenges required “an urgent call to action”.

That included higher levels of military preparedness and accelerated capability development, they wrote.

“Intense China-United States competition is the defining feature of our region and our time. Major power competition in our region has the potential to threaten our interests, including the potential for conflict,” they wrote.

“Australia does not have effective defence capabilities relative to higher level threats.”

The defence force has been given five main jobs: defend Australia and the immediate region; deter an attempt to project power against the nation; protect economic connections such as trade routes; contribute to collective security with partners; and maintain the global rules-based order.

The government has responded to the review by immediately cancelling six projects, delaying a further six and redefining the scope of 21 others.

The government will slash the majority of new infantry fighting vehicles from 450 to 129 and boost long-range missile capabilities from a maximum range of 45km to more than 500km.

It has also given in-principle support to equipping fighter jets with long-range, anti-ship missiles.

“The government is making the hard decisions necessary to cancel or reprioritise defence projects and activities no longer suited to our strategic circumstances,” the prime minister and defence minister said in a statement.

Some of the review’s more than 100 recommendations, the specifics of others and some government responses have been kept classified.

The six new priority areas include the acquisition of nuclear-powered submarines, developing the ability to accurately strike targets at longer-range and building ammunition locally and improving defence’s ability to operate from northern Australia.

The headline cost of reprioritising projects is $19 billion over four years, which will be offset through cancelled projects and savings already found by changing to nuclear-propelled submarines through the AUKUS pact.

Growing and retaining a highly skilled defence force, working closely with Australian industry and deepening diplomatic relations in the region including through ASEAN and the Pacific Islands Forum have also been identified as priorities.

An inaugural national defence strategy will be developed in 2024 and updated every two years.

An independent review of the navy’s combat fleet – which the review said must have “enhanced lethality” – will also be conducted towards the end of next year, while options for guided weapons and explosives will be delivered by the middle of 2024.

Better preparing the defence force to handle natural disasters and an increase in fuel security, including the transition of defence to clean and renewable energy, have also been recommended.

-with AAP