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