Official report claims "significant drop" in stubble burning in neighbouring states. Delhi is currently suffering with the pollution generated from the local sources.

The Air Quality Index (AQI) of Delhi on Sunday was 311, considered 'very poor', while on Saturday it was 267 or 'poor', on a scale of 0 to 500.

The major pollutant PM2.5 or particles with diameter less than 2.5mm also intensified over the day as the Westerly winds brought along moisture.

"Air quality is 'very poor' and expected to remain in the same category, with a gradual increase for the next three days as surface winds will be declining slowly," said a forecast by System of Air Quality and Weather Forecasting And Research (SAFAR).

SAFAR said that high humidity is unfavourable for dispersion of the pollutant.

"Delhi currenlty is polluted with its own pollutants. Stubble burning has negligible effect on it," said Mahesh Palawat, a director at private weather forecasting agency Skymet.

With wind speeds set to fall till November 20, the pollution may rise.

"However, air quality will improve with Delhi receiving fresh north-westerly winds from November 21," Palawat added.

The average presence of the major pollutant PM2.5 was 163 microgrammes per cubic meter in Delhi. Across over 40 regions in the National Capital Region (NCR) it was 160.

Across NCR, Gurugram with an AQI of 255 or 'poor' had the cleanest air. The AQI was 335 in Ghaziabad, 313 in Greater Noida, 336 in Noida and 308 in Faridabad.

SAFAR has issued an advisory cautioning people in Delhi to avoid outdoor physical exercises.