Australian Prime Minister Scott Morrison has taken a serious knock in the polls, conceding he was in the wrong when he took a flight to Hawaii with his family in the midst of Australia's bushfire crisis as more lives continue to be lost.

Morrison fronted the media after weeks of criticism over his family holiday, telling the ABC's Insiders programme on Sunday that he could have "handled things on the ground much better".

Kangaroo Island off South Australia is on notice as a massive bushfire is described as 'virtually unstoppable'. Photo / South Australian Country Fire Service

The Prime Minister also announced on Sunday he would "continue to evolve" his government's climate change policy while also flagging a royal commission into this summer's tragic and ongoing events.

Late last night, Morrison's approval ratings were sent tumbling as the Coalition fell behind Labor in The Australian's latest Newspoll survey.

The poll showed Morrison's approval rating fell eight points from 45 per cent to 37 per cent while those dissatisfied rose 11 points from 48 per cent to 59 per cent.

It comes as the death toll from bushfires climbed to 28 when a Victorian firefighter was struck and killed by a tree on Saturday.

Bill Slade, 60, was fighting fires in the Gippsland region near Omeo where he had worked as a firefighter for 40 years.

Wonthaggi father-of-two Bill Slade, 60, was struck by a tree while working at the edge of a fire at Anglers Rest near Omeo on Saturday. Photo / supplied

He was one of the region's longest-serving firefighters and leaves behind his wife Carol and the couple's children Steph and Ethan. Premier Daniel Andrews and Morison both offered condolences to Slade's family on Sunday.

"He was much loved, an absolute mentor to many many people and we send our best wishes to Carol and his two kids, his broader family, friends, and his Forest Fire Management Victoria family," Andrews said.

Cooler conditions and some rain in NSW and Victoria helped slow out-of-control fires but they continue to burn and are likely to continue burning for several weeks.

The sky turns red from the fires in Omeo, Bruthen, Australia. Photo Darrian Traynor, Getty Image

More than 1.3 million hectares have been razed since November 21, while 286 homes and 400 other buildings have been damaged.

Morrison said on Sunday that the scale of the bushfires was "unprecedented" and had created a situation in which Australians were demanding a greater response from the federal government than had been provided in the past.

"That was not something that was recommended going into this fire season," he said.

"There is a very new appetite, a very new expectation."