The biggest wildfire ever recorded in New Mexico was still defying efforts to contain it on Monday.

So far it's burned its way through almost 100 hectares in the southwest of the state.

There's no sign of it stopping yet.

Firefighters said they had contained about 17 per cent of the inferno.

They admit they still have a long way to go.

Fire lines were being built to stop the flames reaching communities.

Hot windy weather and the harsh terrain are adding to the difficulties.

The fire was started by lightning on May 16th.

Paul Chapman, Reuters