The air quality of the national capital remained in the "severe" category on Saturday morning with the AQI settling at 407 at 9 am, according to the Sameer app that provides hourly updates of the national AQI published by the Central Pollution Control Board (CPCB).

An air quality index (AQI) between zero and 50 is considered "good", 51 and 100 "satisfactory", 101 and 200 "moderate", 201 and 300 "poor", 301 and 400 "very poor", and 401 and 500 "severe".

On Friday, the Delhi government banned private BS III petrol and BS IV diesel vehicles, prohibited the entry of interstate non-electric-CNG buses, certain categories of construction activities and staggered government office timings, as the city choked under 'severe'-category air pollution.

The restrictions were imposed under stage III of the Graded Response Action Plan (GRAP) announced by the Commission for Air Quality Management (CAQM) on Thursday.

Delhi recorded a minimum temperature of 15.3 degree Celsius, 1.8 notch above the season’s average, the India Meteorological Department said.

The weather department has predicted mainly clear sky with smog or shallow fog likely in the morning or night on Saturday. The maximum temperature is likely to settle around 33 degrees Celsius. The humidity at 8.30 am was 94 per cent.

Private BS III petrol and BS IV diesel vehicles were banned from roads with violations inviting a penalty of ₹20,000. Diesel and petrol inter-state buses from the NCR cities to Delhi are also banned.