SINGAPORE/KUALA LUMPUR – Singapore's National Environment Agency (NEA) on Monday warned of a possible deterioration in air quality this week after an increase in hotspots and smoke haze activity in the region.

"We have observed an escalation in hotspot and smoke haze activity over the weekend, with hotspots and dense smoke plumes detected mainly in Kalimantan and southern Sumatra. Some smoke plumes were also observed in Riau," the NEA said in a Facebook post.

The agency expects dry conditions to persist during the week. With prevailing winds blowing from the south or southeast, it noted that there could be occasional periods of haze affecting Singapore. 

M'sia, Indonesia to cooperate on El Nino, haze

Meanwhile, Malaysia will cooperate with Indonesia to step up preventive and early firefighting measures to cope with the El Nino phenomenon, Malaysian Natural Resources and Environmental Sustainability Minister Arthur Joseph Kurup said on Monday.

The issue of transboundary haze currently affecting the region is also a priority for both countries, Arthur said in a statement following a telephone call with Indonesia's Environment Minister Mohammad Jumhur Hidayat.

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"With the El Nino phenomenon expected to intensify toward October this year, coinciding with the Southwest Monsoon, both our countries are committed to stepping up preventive measures and early firefighting efforts," he said.

Arthur said that in the spirit of good neighborliness and ASEAN solidarity, Malaysia is ready to assist Indonesia at any time should assistance be required, particularly in swiftly putting out fires.

Also on Monday, a total of 12 areas in Malaysia recorded unhealthy Air Pollutant Index (API) readings as of 2 pm local time, according to the Air Pollutant Index Management System.

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The worst-hit is the northern Borneo state of Sarawak with six areas breaching the unhealthy threshold, with Serian district recording the highest reading nationwide at 193, followed by the state capital Kuching (179), Samarahan (174), Sri Aman (156), Bintulu (151) and Mukah (114).

According to the country's air quality rating, an API reading of zero to 50 is "good," 51 to 100 is "moderate," 101 to 200 is "unhealthy," 201 to 300 is "very unhealthy," and 301 and above is "hazardous."