The fires are an annual problem in southeast Asia, and are set by locals clearing vast tracts of forest to make way for palm oil and pulp and paper plantations.
International help to assist Indonesia in combating forest and agricultural fires cloaking Southeast Asia in haze has begun to arrive on Sumatra island.
Seven helicopters and four aircraft from Indonesia, Malaysia and Singapore are currently operating to extinguish fires in the south Sumatra province, one of the worst-affected areas by the slash-and-burn land clearing practice.
The Indonesian government initially insisted it would not accept help from other countries to battle the forest fires.
However, the smoky haze from the land-clearing fires in Sumatra and part of Borneo island has been exacerbated by the current dry season caused by the El Nino weather phenomenon.
Indonesia has faced growing pressure in the past few weeks to contain the annual haze.
Last week the Indonesian president, Joko Widodo, asked other nations - including China, Singapore, and Russia - for help to put out the fires.
"I've already called the coordinating minister and the head of the National Disaster Management Agency and given them a target of about two weeks (to contain the fires), which could be less as our water-bombing capacity is now bigger, so hopefully the situation can be resolved sooner."
Australia says it will send a military aircraft to help Indonesia fight forest fires.
The Hercules L100, which is capable of dropping up to 15,000 litres of water, is expected to arrive in Indonesia's Palembang on Sumatra island early next week.
The Australian ambassador to Indonesia, Paul Grigson, says it's a larger plane than originally requested by Indonesia.
"The Indonesian request was for a 10,000-litre aircraft: we sent a bigger plane. This is a very big plane as I said, able to drop 15,000 litres in a few seconds. This was the most important element from Indonesia's request to us."
The latest data from Indonesia's National Disaster Management Agency, BNPB, shows Sumatra is one of the worst affected areas, with 613 out of 726 total hotspots on the island in western Indonesia.
The smoke has also pushed up pollution to dangerous levels across parts of Indonesia, Malaysia, Singapore and southern Thailand.
The Disaster Management Agency says around 25.6 million Indonesians have been directly exposed to the haze and thousands of people are suffering from respiratory tract infections as a result.
The agency's chief, Willem Rampangilei, says he hopes for rain to help douse the fires by early November, when the northeast monsoon usually starts.
"Smoke can only be put out by heavy rainfall or spraying enough water, if there's not enough water it will produce smoke, so it needs time (to be put out). We are hoping by the end of October or early November, the haze problem will be resolved."
