British Prime Minister Boris Johnson has also promised Brazil an $18 million donation to help.
But Mr Morrison says Australia would merely keep an eye on pledges towards the disaster.
"That should be well within the means of those countries for which this is their primary sphere," he told reporters in Biarritz, France, where the G7 summit was held.
"This is not directly in our sphere but it is the lungs of the world and we understand it's important."
Australia has a track record of responding first to disasters within its region.
"The Boxing Day tsunami, things like this, Australia has been quick out of the blocks," he said.
"Whether they're in Indonesia or elsewhere in the Pacific, we are the first responders and Australia takes our responsibility in our sphere very seriously."
Brazilian authorities have not asked Australia for help but a Department of Foreign Affairs spokeswoman told AAP on Monday the Australian embassy in Brazil's capital Brasilia was keeping watch with "deep concern".
"The world's rainforests are a wealth of natural heritage and biodiversity. Australia knows too well the human and natural cost of fire," she said.
Mr Morrison acknowledged Australia did have a lot of expertise and equipment to fight large fires but noted the domestic summer fire season was approaching and that capability would be needed at home.
Labor's foreign affairs spokeswoman Penny Wong has said the government should be proactive in offering practical help, arguing Mr Morrison shouldn't "sit on his hands until he's asked".
Overseas requests for help from Australian firefighters typically occur through diplomatic channels.