SYDNEY (REUTERS, AFP) - Australia will hold a wide-ranging inquiry into the causes of recent bush fires that killed 33 people and razed an area the size South Korea, Prime Minister Scott Morrison said on Thursday (Feb 20).

Australia has been battling hundreds of blazes that began in September - an unusually prolonged summer wildfire season that was fuelled by three years of drought, which experts have attributed to climate change.

With firefighters now able to contain the several dozen fires still alight, Mr Morrison said a six-month Royal Commission will be tasked with finding ways to improve Australia's preparedness, resilience and response to natural disasters.

Mr Morrison said it would also be asked to consider establishing new powers for the federal government to declare a national state of emergency, which he argued would allow a faster response to fires.

"This Royal Commission is looking at the practical things that must be done to keep Australians safe and safer for longer in hot dry summers - conditions in which Australians will live into the future," Mr Morrison told reporters in Sydney.

The inquiry will be led by former Air Force chief Mark Binskin, along with retired Federal Court judge Annabelle Bennett and environmental lawyer Professor Andrew Macintosh.

Mr Morrison said they would be required to report their findings by 31 August, "so recommendations can be acted upon before our next bush fire season".

Australia has seen dozens of inquests into the causes of bush fires and steps that could be taken to mitigate them, with mixed results.

Many measures from the dozens of inquests going back to the 1930s have still not been implemented.

The opposition Labor party accused Mr Morrison of trying to "shift attention to the things that he thinks are politically convenient to talk about" rather than "actually fixing climate change and getting emissions under control."

The most recent crisis has sparked calls for Australia's conservative government to take immediate action on climate change, with street protests urging Mr Morrison to reduce the country's reliance on coal.

Mr Morrison has stoked widespread public anger by refusing to directly link the bush fires to climate change, insisting removing flammable vegetation is "just as important, if not more".

His management of the fires was already under the microscope after he was forced into a rare public apology for taking a holiday to Hawaii in November.

Under mounting pressure, Mr Morrison in January deployed 6,500 military reservists to support state authorities - which he said created a "constitutional grey zone".

Managing bush fires is the responsibility of state governments and fire services.