Forty firefighters from New Zealand have been recruited to help to battle wildfires raging across California.
Internal Affairs Minister Rick Barker said the contingent would be made up of firefighters from the rural fire service and local authorities.
The deployment was expected to last at least five weeks.
Don Smurthwaite, a spokesman for the National Interagency Fire Centre in Boise, Idaho, said the Californian blazes had consumed more than 273,418ha of forests and grasslands.
US authorities already have nearly 19,000 firefighters battling 323 fires threatening 15,751 homes and buildings and thousands of people have been evacuated.
On June 21, an electrical storm sparked about 1700 fires in a 48-hour period, bringing an early start to the California fire season, which usually does not begin until late August.
This has created problems for the US because the fire season in the rest of the western states is under way and crews that would start the Californian season fresh have already been in the field for six to eight weeks.
Mr Smurthwaite said: "Australia and New Zealand are a really good fit because their firefighters are trained to roughly the same standards and use an incident command system that parallels ours. Plus it is the dead of winter so there is no pressing need for them to stay at home."
This is the fifth time that America's National Multi-Agency Co-ordinating Group has asked New Zealand and Australia for help.
In 2006 New Zealand had 29 firemen battling US wildfires.
