Kuala Lumpur (ANTARA News) - Malaysia's health minister Monday warned of resentment against Indonesia and economic fallout as thick haze caused by Indonesian forest fires caused a sharp deterioration in air quality.

Malaysia also issued a hazard warning for ships plying the Malacca Strait after haze caused visibility to drop along the vital waterway.

Indonesia has been blamed for much of the haze from illegal land-clearing fires on Sumatra and the Indonesian portion of Borneo, and Health Minister Chua Soi Lek called on the country to step up its efforts to tackle the crisis.

"We hope that the Indonesian government becomes more proactive in helping to solve this problem, because it not only causes resentment among our people, it also has economic implications," Chua was quoted by AFP as telling reporters.

"In terms of tourism, outdoor activities, even hawkers (street vendors) at night are affected," he said.

Visibility dropped in eastern Sarawak state on Borneo island and parts of peninsular Malaysia's west and south, while the meterological department said it be below five kilometres (three miles) in the Malacca Strait until Thursday.

"This situation is hazardous to ships without navigational equipment," it said in a statement.

Environment department data showed air quality was at unhealthy levels in 14 areas in the country's west and south, including Kuala Lumpur and the administrative capital of Putrajaya.

In Kuala Lumpur, where the Air Pollutant Index hit an unhealthy reading of 159, people wore face masks on the streets to ward off sore throats and respiratory complaints.

Streets were largely empty in Putrajaya, which registered a reading of 171, as people complained of stinging eyes and hoarse throats.

A reading on the index between 101 to 200 is unhealthy, while 201 to 300 is very unhealthy.

Foreign Minister Syed Hamid Albar said that Southeast Asian nations had to work together to combat the recurring crisis, and formulate a plan of action rather than merely signing agreements which achieved little.

"Since we are suffering together, let's try and solve it together, in terms of action," he told reporters.

"It is one of those unfortunate things that we are not able yet to translate into something meaningful. There must be a political position."

In a sign of frustration with Jakarta, Chua said Indonesia was well aware of the consequences of the haze, which is an annual blight on the region.

"The Indonesian government is fully aware of the problem that they have created for all of us here in ASEAN, more so for Singapore and Malaysia, as immediate neighbours," he said.

In Indonesia, light rains cleared one haze-choked region on Monday but poor conditions persisted in other areas with air travel disrupted and residents forced to don face masks outside.

Singapore has also been hit badly by the fog-like haze this year, with authorities issuing a health advisory Saturday suggesting people should cut outdoor activity, although the situation there improved on Sunday.