Annual battle: Choking Singapore blasts Indonesia

Anger is rising in Singapore as a thick haze engulfs the city-state, causing schools to be shut down.

This morning, the Pollutants Standards Index (PSI) hit 341 - the highest level this year.

Singapore foreign minister K Shanmugam said late on Thursday that Indonesia was showing "complete disregard for our people, and their own".

The haze is caused by forests fires in Indonesia used to clear land for palm oil and rubber plantations.

The annual problem has been causing hazardous pollution levels across the region for weeks. Any PSI reading over 300 is considered hazardous to health.

Indonesia has repeatedly said it is taking steps to prevent illegal forest burning. It has deployed troops to tackle the blazes, in Sumatra and on Indonesian Borneo, and says it is investigating 27 companies suspected of involvement in fires.

But Shanmugam said on Facebook, "We are hearing some shocking statements made, at senior levels, from Indonesia," noting that PSI readings had reached nearly 2,000 in parts of Indonesia.

"How is it possible for senior people in government to issue such statements, without any regard for their people, or ours, and without any embarrassment, or sense of responsibility?"

He did not name any officials, but Indonesian vice-president Jusuf Kalla has angered some in recent weeks by saying Indonesia's neighbours should be grateful for the air quality for the other 11 months of the year.

Singapore and Indonesia use the Pollutants Standards Index (PSI) to measure air quality, while Malaysia uses the similar Air Pollutants Index (API). On both indices, a reading that is above 100 is classified as unhealthy and anything above 300 is hazardous.

Emergency measures enacted in Singapore include the closing of all primary and secondary schools for the first time this haze season.

Free masks are also being distributed at community centres for the elderly and vulnerable.

Fast-food chains including McDonalds, KFC and Pizza Hut suspended their food delivery services on Thursday citing concerns for the health of their drivers.

Later today the PSI dipped back below 300 and delivery services have since resumed.