Singapore cautioned against the return of haze from forest fires in neighbouring Indonesia today, a month after air quality in the city-state reached hazardous levels.

The National Environment Agency (NEA) warned that satellite data showed “a marked increase in the number of hotspots in Sumatra”, with more than 250 counted on Sunday and yesterday.

Agency head Ronnie Tay had contacted Indonesian authorities to register Singapore’s concerns and offer help in tackling the problem, the agency said.

Tay “sought an urgent update of Indonesia’s efforts to tackle the fires there and urged Indonesia to take immediate action,” the statement said.

He offered Singapore’s help in detecting and suppressing the forest fires, and the use of an aircraft to help in cloud seeding operations that aim to create rain.

Jakarta assured Singapore that it was monitoring the situation and taking action to suppress the fires, the statement added.

Haze from forest fires on Sumatra island mostly affects Indonesia’s Riau province, Malaysia and Singapore during the dry months of June to September. The fires are started illegally to clear land quickly and cheaply for agricultural use.

Singapore’s Pollutant Standards Index peaked at 401 on June 21 during the latest period of haze. Anything over 300 is considered hazardous.

- dpa