Jakarta – Civil servants in an Indonesian province have been offered two days off work if they help douse land-clearing fires which have blanketed vast areas with choking haze, officials said.

The acrid smoke has enveloped huge swathes of Indonesian Borneo and Sumatra in recent weeks as well as Singapore and Malaysia, triggering criticism that Jakarta has done too little to combat the annual environmental disaster.

A spokesman for Central Kalimantan province, Dendol Toepak, said the offer of a two-day holiday was made by Governor Agustin Teras Narang.

Toepak said the governor Tuesday launched his public drive to control the fires by attending a fire-fighting operation along with more than 200 civil servants, soldiers and police.

"Today (Tuesday) the campaign is taking place in Palangkaraya city and five districts. Tomorrow it will be launched in the eight other districts," he said.

In Palangkaraya alone four spots were designated by local authorities for volunteers to help out at, although local ElShinta radio reported that water shortages were hampering efforts to wipe out the fires.

Visibility was less than 100 metres (yards) in the city, weather officials said.

In Sumatra's Jambi, another of the badly-hit provinces, visibility was at just 300 metres at 10:00 am (0300 GMT) and flights to and from the airport, which serves domestic routes only, were cancelled indefinitely, Heri Budi from the meteorology station there told AFP.

Jakarta has outlawed land-clearing by fire but weak enforcement means the ban is virtually worthless, and President Susilo Bambang Yudhoyono last week apologised to both Malaysia and Singapore for the effects there.

On Monday, Singapore's pollution index soared into the unhealthy range and authorities maintain a health advisory recommending that people avoid vigorous outdoor activity.

The haze also sharply reduced visibility at major airports in Malaysia.

Environment ministers from Brunei, Indonesia, Malaysia, Singapore and Thailand met last Friday to discuss the crisis and urged Jakarta to ratify a 2002 treaty on haze.