Sydney  - More than 1,000 of Australia's volunteer firefighters were in action Saturday as crews battled 60 of forest blazes in the sweltering south-east where a decade of drought has left tinderbox conditions.

A total ban on open fires was declared in New South Wales, where Rural Fire Service (RFS) assistant commissioner Rob Rogers invoked the first "Catastrophic" or "Code Red" warnings that beseech householders to flee their homes rather than stay and fight the flames.

"We need people to avoid those activities that could potentially start a fire today," he said. "Everybody's got all hands on deck to do what they can to get these fires under control."

Rogers said the RFS had 400 fire trucks and 70 aircraft ready to tackle blazes that threatened homes.

The Blue Mountains National Park, a popular day-trip for tourists visiting Sydney, was closed because of fires lit by lightning strikes on Friday.

The Catastrophic category was introduced after retired judge Bernard Teague's report on February's deadly forest fires north of Melbourne. The Black Saturday fires killed 173 people, destroyed 2,000 properties and blackened 430,000 hectares.

Teague said the current warning system "did not make it clear that those who chose to remain were risking their lives."

He said the safest option was to leave well in advance of the fire front but stopped short of advocating compulsory evacuation. (dpa)