Australian Prime Minister SCOTT MORRISON says Australia's government and institutions are being targeted by ongoing sophisticated state-based cyber hacks.

Prime Minister MORRISON said the cyber attacks were widespread, covering "all levels of government" as well as essential services and businesses.

He declined to identify a specific state actor and said no major personal data breaches had been made.

He said the attacks have happened over many months and are increasing.

The prime minister said his announcement was intended to raise public awareness and to urge businesses to improve their defences.