Kuala Lumpur (ANTARA News) - Air quality deteriorated on Sunday along coastal areas of Malaysia's side of Borneo island caused mainly by open burning from Indonesia, officials said.

The Air Pollutant Index on the Department of Environment's website reached 123 in the town of Sri Aman in the eastern Sarawak state, where air quality has been at unhealthy levels for the past week.

An index within 101-200 level are deemed to be unhealthy.

The index was almost unhealthy in the state's capital of Kuching which recorded a reading of 94, and in the towns of Sarikei and Petra Jaya, where it reached 94 and 97 respectively.

Visibility plunged to below 300 metres (0.2 miles) in Sri Aman, 500 metres in Kuching and 2.0 kilometres in Sibu at midday. Normal levels are more than 10 kilometres.

Kuching airport officials said there had been no impact so far on flights.

An official from the Meteorological Department in Kuching told AFP strong southerly winds were blowing haze and smoke particles from forest fires in Indonesia's Kalimantan.

"Currently we are experiencing active tropical storm activities in the western pacific area and in the South China Sea," the official said.

"Whenever we have a tropical storm, it will pull all the moisture and strengthen the winds coming from the southern side of Borneo island," he
added.

He said the meteorological department predicted more rains for the next two weeks but the strong south westerly winds will still blow smoke from
Kalimantan.

"However once the south-western season completely ends in late October, the rainly season will start so on Malaysia's side, conditions will improve," he

Burning in Indonesia and parts of Malaysia to clear land for crops causes an annual haze that afflicts the region. Plantation owners usually bear the brunt for the burning activities.