Australian Prime Minister Scott Morrison has approved the first stage of a A$3 billion investment in the country's Special Forces.

Project GREYFIN will see the money invested in different areas, including training and equipment, over the next 20 years.

"I’ve always said keeping Australians safe is my Government’s number one priority.  That’s why we’re ensuring the men and women in our Special Forces have the equipment and training they need to succeed in their operations," said Mr Morrison.

"Global threats will continue to evolve in ways which threaten Australia's interests. This funding will ensure our Special Forces have cutting edge capabilities to stay ahead of those who might threaten Australia's interests."

The Special Forces will get A$500 million in the first stage. Defence Minister Linda Reynolds said that money will include investment in technology and innovation.

"This first stage of funding enables our Special Forces to engage with intelligence, science and technology, and innovation organisations to ensure future threats and opportunities are assessed, to make sure we are delivering them the capability they need in the future," she said.

The government said Project GREYFIN would provide significant opportunities for Australian defence industries.