SYDNEY - Singapore is deploying two helicopters to assist Australia's efforts to respond to a bush fire crisis that has killed 25 people, burned vast swathes of the country and destroyed about 2,000 homes.

Australian Prime Minister Scott Morrison expressed thanks to his Singaporean counterpart, Mr Lee Hsien Loong, for the offer of support, saying two Chinook helicopters would travel to a staging point in the state of Victoria.

"Two Singapore Chinooks are preparing to deploy from Northern Australia to East Sale which is our forward staging point in Victoria for those operations," Mr Morrison told reporters on Monday (Jan 6).

Singapore Defence Minister Ng Eng Hen said on Facebook that the two Singapore Chinooks took off from Oakey with 42 Singapore Armed Forces (SAF) personnel bound for East Sale on Tuesday morning.

"Our Chinooks will bring in firefighting and relief supplies and also help evacuate residents from the affected areas," Dr Ng said.

"Australia has welcomed SAF troops to train there for decades, and in their time of great need, it's only natural that the SAF do our best to help their people and communities affected by this unexpected natural disaster," he added.

Hundreds of fires are still blazing across Australia. Military aircraft and ships have been assisting with evacuations of residents and with providing supplies and relief.

Singapore operates Chinooks in Australia for training purposes under a training agreement between the two countries.

New Zealand said it is sending about 80 Defence Force personnel and three Royal New Zealand Air Force NH90 helicopters.

Fires have ravaged more than 8 million hectares of land across the country, an area nearly the size of Austria, and leaving some towns without electricity and mobile coverage.

Police on Monday confirmed the death of a 71-year-old man on the south coast of New South Wales (NSW) state who was reported missing on Dec 31.

Cooler weather for a second day and some light rain across the south-east of Australia brought some relief for fire-fighters and those displaced. But large areas of thick smoke were hampering rescue efforts.

Victoria state Premier Daniel Andrews said about 400 people were airlifted on Sunday (Jan 5) out of Mallacoota, a small, coastal holiday town near the border with NSW. “We had a plan to airlift another 300 out today. Sadly smoke means that is not possible,” he said.

Forty-one US firefighters are in Victoria with a further 70 from Canada and the United States expected to join on Jan 8, the Victoria Country Fire Authority said on Twitter.