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Firefighters are tackling a growing tussock fire north of Taupo, stretching local fire services that need to look after their own tinder-dry patches before they can even think about sending crews to help fire-ravaged Australia.

A third helicopter has been scrambled this afternoon to help two helicopters with monsoon buckets and fire crews already battling the tussock fire at Kinloch, near Taupo.

Ten fire appliances, including two water tankers from around the Bay of Plenty and 40 firefighters on the ground are working on containing the flanks of the fire.

The fire is believed to have been started about 11.30am from a spark from hay making machinery.

Fanned by a 10km/h wind, it spread quickly into tussock grass and has grown to 12 hectares. It is threatening a stand of pine trees about 500m away.

Meanwhile, the Gisborne district fire risk is described as the worst seen by fire authorities in more than 10 years .

That meant local firefighters will not join a national contingent of 100 travelling to help out their Australian peers battling out-of-control fires, the Gisborne Herald reported today.

Australian bush fires have killed more than 100 people in what is described as the country's worst natural disaster.

Gisborne rural firefighters had gone over to help in similar situations in the past but were simply "too stretched" this year, said principal rural fire officer Don Scott.

"There ain't no way we are going anywhere," Mr Scott said. "We are stretched like a rubber band."

Firefighters were struggling to keep up with fires throughout the region, including four yesterday afternoon in four hours.

In Otago, firefighters said they also would be nervous about going to fight bushfires in Australia while Otago itself was so dry.

A total fire ban is in place in parts of the province and it could be extended over the next few days, the Otago Daily Times reported. While New Zealand firefighters have not yet been asked to help out in Victoria, Dunedin City Council principal rural fire officer Graeme Still said he would have to think very carefully before committing the team of six he took to Australia three years ago.

"Our fire danger's a bit high so I don't think we'd like to be travelling too far. Our own back door's pretty dry at the moment."

National rural fire officer Murray Dudfield said New Zealand's own fire risk would be taken into account if Australia requested help.

The fire risk is now "extreme" in parts of the east coast of both islands.

In 2006, New Zealand sent 85 firefighters to Australia.

Eleven were injured and forced to run for their lives near Mansfield in northeast Victoria, when they were caught in a wildfire flare-up.

While he would not be surprised to get the call from Australia, particularly if the fires continued for a long period, "it wouldn't be very prudent to send people away with the fire danger the way it is at the moment", Mr Still said.

- NZPA