Northern Territory emergency services are battling a bushfire in the Barkly region, more than 9,300 square kilometres in size.
Crews have been called in from South Australia and three extra fire bombers are on the ground in Tennant Creek.
The fire is burning on the Barkly tableland east of Tennant Creek, about 500 kilometres north of Alice Springs.
Chief Fire Controller Tony Fuller said the blaze was "roughly three to four times the size of the ACT", sitting between Epenerra and the Barkly Highway.
"We've had large [fires] in the past, but this is the largest one I've had to deal with," he said.
Mr Fuller said while there was no risk to residential properties, some pastoral leases were under threat including a cattle station north of the Barkly Highway.
"Station workers have been working really hard for the last few days," he said.
"They've managed to put some control lines in, which we hope will stop it moving into their property further."
A fire ban has been declared today for the Darwin, Adelaide River, Gregory South-East and Barkly North fire weather forecast areas.
Authorities have been closing and re-opening the Barkly Highway between Barkly Homestead and Threeways Roadhouse based on the latest conditions, which are changing quickly.
"We had one incident in particular with a cotton truck that we thought we were going to lose," Mr Fuller said.
"But thanks to the crews on the ground, they managed to stop that cotton truck going up in flames."
Mr Fuller said emergency services were working with transport companies around impacts to road access, but said he didn't anticipate the fire would impact supermarket shelves.
"The main concerns at the moment are our main highways and the potential for livestock [fatalities]," he said.
Mr Fuller said some cattle stations in the NT were possibly carrying more stock than usual due to Indonesia's temporary export ban on cattle, which was lifted on Friday.
The NT Emergency Management Council (TEMC), co-led by NT Police Commissioner Michael Murphy, has been meeting to assess the unfolding situation.
In a statement, Commissioner Murphy said "this is a blaze with a fire edge extending hundreds of kilometres".
"Our thoughts and thanks are with the pastoralists who are working incredibly long hours protecting their property and stock" he said.
"We thank all the hard working frontline personnel leading, surveying and putting in mitigation strategies to minimise the impact of this large and uncontrolled fire. "
Story by: Samantha Dick
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