The haze situation is still at the worrying level as Air Pollutant Index (API) readings at 5pm did not show any signs of significant improvement.

Department of Environment (DoE) data revealed that 18 areas were affected by the haze, comprising 14 areas where air quality is considered as "unhealthy", two areas where APIs are between 201 and 300 (Very unhealthy) and another two areas deemed as hazardous.

The worsening haze situation has also prompted the goverment to shut down all schools in Kuala Lumpur, Selangor, Melacca, Kuantan and parts of Johor.

Muar remained as the most affected area with API of 507. Earlier, the town posted APIs of 746 and 690, as of 7am and 11am, respectively.

Pasir Gudang, Kota Tinggi and Larkin Lama, which were registering API of over 100 this morning, are now having APIs of 96, 91 and 89, respectively.

While parts of Johor are seeing signs of improvement, key areas in Selangor and Federal Territory are experiencing worsening air quality.

Banting, Port Klang, Petaling Jaya and Shah Alam - which registered APIs of between 102 and 188 this morning - are now recording APIs of between 130 and 214.

Putrajaya, Cheras (KL) and Batu Muda (KL) are now having APIs of above 134, versus the high of 102 this morning.

Meanwhile, Singapore has been experiencing moderate air quality level for most part of the day -- with APIs of under 100 between 10am and 7pm.

However, the government told its citizen to be prepared for worsening condition in the coming days.