Rural Fire Service (RFS) crews responded to initial reports of "fire running quite hard" at Burrewarra Point Reserve, Guerilla Bay at about 7.30pm, on Monday, October 21.

RFS spokesman Marty Webster said six RFS crews with the support of Batemans Bay Fire and Rescue NSW rushed to blaze.

"When we arrived, we found the fire on the cliff face, south to the light house," Mr Webster said.

No properties were under threat.

Mr Webster said the chopper is currently "water bucketing the fire to make sure it's fully extinguished".

"Much of the cliff face is not safe for firefighters, it's a tricky location," he said.

"We are expecting some rough weather later in the week.

"It will be an efficient operation for the aircraft using ocean water to extinguish the fire."

Mr Webster said the blaze spread about three hectares through coastal scrub on the cliff. Mr Webster said the cause of the fire is unknown at this stage and believed it could be suspicious.

Malua Bay, Broulee, Mogo and Surf Beach RFS crews attended.