A thick haze from forest and ground fires has blanketed several Indonesian regions on Borneo island, choking residents and disrupting road and air traffic.

One scheduled landing was cancelled Tuesday morning at the airport at Palangkaraya in Central Kalimantan and another cancellation was likely later on, said an official there.

The official, Ngurah, said visibility remained at around 500 metres even after the sun came out in mid-morning.

"It has been very slow to thin out today. Visibility was around 200 meters early this morning but despite the presence of the sun, visibility is now still at 500," Ngurah said. He said people were suffering from watering eyes and found breathing painful.

Visibility was also around 500 meters at the airport at Pontianak in neighbouring West Kalimantan province. But Sudariyanto, the officer in charge, said four flights had landed and taken off again despite the low visibility. "There is no longer a ban on flying when visibility is at a minimum level so now it all depends on the pilot, whether they think they can do it," Sudariyanto said.

Take-offs and landings had previously been banned when visibility was below 1,500 meters.

Sudariyanto said weather officials predicted the haze would linger for some time in the absence of wind or rain in the area. He said vehicles were using headlights during the day and masks were essential, especially for motorcyclists.

The haze, partly from fires started illegally to clear land for replanting, is an annual problem for Indonesia and its neighbours.

In neighbouring Malaysia health authorities have put hospitals on alert for treatment of possible respiratory complications.

The haze, caused by fires in Kalimantan and on Indonesia's Sumatra island, has also disrupted internal flights in Malaysia's Sarawak state on Borneo.

In 1997 and 1998, choking haze caused by forest fires in Indonesia blanketed parts of Southeast Asia for months, causing serious health problems and traffic hazards and disrupting airline schedules.