Indonesia's leading environmental watchdog on Saturday urged the government to declare a state of emergency and criticized officials' slow handling of the haze crisis caused by hundreds of forest fires.

"The most important thing that the government should do is to declare a state of emergency, take action to extinguish the fires and tell the public what to do because this concerns the safety of many people," said Chalid Muhammad, executive director of environmental group Walhi, in a statement.

Haze from forest fires and blazes lit to clear land on the Indonesian island of Sumatra has smothered parts of neighbouring Malaysia for the past week, prompting Kuala Lumpur to declare a state of emergency in two towns.

Muhammad urged the Indonesian government to revoke the business licenses of plantation and timber companies responsible for forest fires and bring them to justice.

"These fires should push the government to... reform its policing of forest management in Indonesia, which in Walhi's view has never been given serious thought, even though forest fires have occurred annually since 1997," the statement said.

Walhi activists have said corruption and law enforcement problems were frustrating efforts to bring to justice plantation companies accused of causing forest fires.

Slash and burn

They said big palm oil producers in Sumatra and Kalimantan, the Indonesian part of Borneo island, had for years used the slash-and-burn method to clear land for their plantations but little action was taken by the government to stop the practice.

Many of the palm oil plantation firms are owned by businessmen from Malaysia, where anger has been mounting over the smothering haze.

Indonesia and Malaysia have agreed to work together to extinguish the fires and Jakarta is hoping other Southeast Asian nations will also help.

Forestry officials said hundreds of rangers had been deployed but were being hampered by the remote locations of the blazes and a lack of water.

Satellite images taken Wednesday showed 993 fires in Riau and North Sumatra provinces, said Israr Albar, a forestry ministry official in charge of forest fires.

In 1997 and 1998, choking haze caused mainly by Indonesian forest fires enveloped parts of Southeast Asia, including Malaysia, for months.