Nationals backbencher Barnaby Joyce has suggested two people who died in NSW bushfires "most likely" voted for the Greens.
Mr Joyce made the provocative comment while blaming the minor party for increasing the threat of bushfires.
"I acknowledge that the two people who died were most likely people who voted for the Green party, so I am not going to start attacking them," he told Sky News on Tuesday.
"That's the last thing I want to do. What I wanted to concentrate on is the policies that we can mitigate these tragedies happening again in the future."
MORE BUSHFIRE COVERAGE
Mr Joyce doubled down on disputed claims the fire service had conducted insufficient hazard reduction burns this year as a result of opposition from Greens councils.
Labor frontbencher Kristina Keneally slammed his remarks during a Senate estimates hearing.
"How does he know who they voted for and why does it matter? They're dead; they died in a bushfire. Isn't that enough?" Senator Keneally said.
Despite raising policy suggestions of his own while the bushfires continued to burn, Mr Joyce criticised Greens MP Adam Bandt for demanding an end to coal production.
"To make these spurious links - that a policy change would have stopped the fire - is so insulting and just completely beyond the pale," Mr Joyce said.
"Because people think, well, maybe if that was the truth I wouldn't be burnt, maybe if that's the truth a good friend of mine would not be dead.
"And you can't do that Adam, you just can't do stuff like that."
His comments are the latest escalation in an increasingly bitter stoush between the Nationals and Greens over the cause of the bushfires.
On Monday, Nationals leader Michael McCormack attacked "raving inner-city lunatics" for linking climate change to the fires.
In return, the Greens labelled the deputy prime minister a "dangerous fool" who was putting lives at risk.
Greens senator Jordon Steele-John branded major party politicians "arsonists" for supporting the coal industry.
His incendiary spray on climate policy came as catastrophic fire conditions gripped NSW.
"You are no better than a bunch of arsonists - borderline arsonists - and you should be ashamed," Senator Steele-John told the chamber on Tuesday.
Australian Associated Press