A fire has closed Skippers Road at Long Gully and Fire and Emergency NZ (FENZ) are warning mountain bikers to stay off the trails in the area.

FENZ Incident Controller Mark Mawhinney said four ground crews and three helicopters are fighting a six hectare vegetation fire which includes retired high country farmland and a large number of dead wilding pine trees.

"We are using helicopters to knock down the active fire while conditions are in our favour this morning, and ground crews will be working to secure the perimeter along the Skippers Road and extinguish hotspots."

The fire is not yet under control, he said.

The moutainbike trails close to the fire include the Skippers Pack Track, which is affected by the fire, the Coronet Loop below Greengate Saddle, the Pack Track and Sack Trail and Atleys Terrace Track.

Mawhinney also reminded people not to fly drones in the area because they are a serious hazard to helicopters.