Australia's Home Affairs boss says the government should manufacture and stockpile critical materials to prepare for national emergencies that result from climate change and disruptions to international supply chains.

Home Affairs Secretary Mike Pezzullo told the Royal Commission into Natural Disaster Arrangements that for emergencies, including natural disasters such as fires or floods, pandemics or even cyber attacks, it would be dangerous to rely on international supply chains – not only for firefighting equipment and materials, but also for items like hand sanitisers.

"Independently of bushfires I think COVID has created a circumstance where we need to seriously think about both domestic manufacturing, in limited and targeted ways, sovereign capability and yes, stockpiles for those geostrategic and geoeconomic reasons," he said.

Mr Pezzullo also made the case for better preparation for disasters with a greater emphasis on national decision making.