Smog in Singapore soared to hazardous levels again on Thursday, prompting government health warnings.

At 13:00 local time Singapore’s pollution standards index (PSI) reached 371, breaking all previous records.

The haze is caused by illegal forest fires in Indonesia’s Sumatra island.

Singapore and Indonesia are to hold an emergency meeting, with Singapore’s environment minister demanding “definitive action” from Jakarta.

Andrew Tan, the chief executive of Singapore’s National Environment Agency, will lead Singapore’s delegation at the emergency meeting, hosted by Indonesia’s foreign ministry in Jakarta.

Dr. Vivian Balakrishnan, Singapore’s Environment and Water Resources Minister, wrote on his Facebook wall that: “Singaporeans have lost patience, and are understandably angry.”

“No country or corporation has the right to pollute the air at the expense of Singaporeans’ health and wellbeing,” he added.

However, Indonesia’s Minister for People’s Welfare, Agung Laksono, said that Singapore was “behaving like a child”.

“This is not what the Indonesian nation wants, it is because of nature,” he said.

Smog in Singapore soared to hazardous levels again on Thursday, prompting government health warnings

Singapore’s buildings have been obscured by the polluted air and the smell of burnt wood has permeated the city-state.

PM Lee Hsieng Loong has asked Singaporeans to “stay indoors where possible and avoid heavy outdoor activities”.

Air traffic controllers in Singapore have been told to work with extra caution given the poor visibility, while McDonald’s has temporarily cancelled its delivery service.

The Singaporean military has also reportedly suspended all outdoor training.

The poor air quality has prompted widespread buying of disposable face masks, leading shops to run out of stock.

A PSI reading above 200 indicates “very unhealthy” air, while a PSI score above 300 is “hazardous”.

Parts of Malaysia have also recorded “hazardous” pollution levels, with over 200 schools in the country’s south ordered to shut.

Malaysia’s Department of Environment has also banned open burning in some states.

Indonesia’s forestry ministry said it intended to use cloud seeding to try to induce rain on Sumatra, AFP news agency reported.

The fires are started to clear land for plantations.

Indonesian officials have suggested that foreign palm oil investors, including Singaporean companies, may bear some responsibility for the fires.

However, several major Singapore-based palm oil companies have denied any involvement.

In 1997 and 1998, many countries in the region were affected by the South East Asian haze, which was caused by smog from Indonesian fires.

Road and air traffic was disrupted, and reports said the smog made around 20 million people ill.

The haze led to an agreement on transboundary haze pollution being approved by the Association of Southeast Asian Nations (ASEAN) in 2002.

However, Indonesia has yet to ratify the agreement.

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