Delhi Chief Minister Arvind Kejriwal on Sunday asserted that there is a "very strong correlation" between stubble burning and pollution in north India as he attributed the improvement in air quality to dip in cases of setting crop residue afire.

Kejriwal and the ruling AAP have been at the forefront of blaming stubble burning in neighbouring Punjab and Haryana as one of the major reasons for high levels of air pollution during winters in Delhi.

"A very strong correlation can be seen between stubble burning and the spike in air pollution in North India. As soon as stubble burning began in the first week of Oct, the AQI started rising. Now that burning is coming to an end, air quality is also improving'" the chief minister tweeted.

His tweet came in reply to pictures of farm fires posted by Jadmine Shah, vice chairman of Delhi Dialogue and Development Commission (DDC), a policy think tank of the city government.

"AQI levels dip to below 200 (Moderate level) in most parts of Delhi, exactly as farm fires reduce to a handful in Punjab, Haryana and UP. These pictures from 10am today say it all," Shah tweeted along with pictures.

In another tweet, the chief minister said, " The stubble burning has stopped and with it, the air quality in Delhi has improved. A few people say that stubble burning contributes only 5 per cent to air pollution in Delhi. So with reduction of only 5 per cent , has the air quality index improved from over 500 to 200? Rather than doing politics on pollution, there is a need to address the issue together with good intentions".

The BJP has been hitting out at Arvind Kejriwal government for "not doing anything" to control air pollution in the past five years and bringing in odd-even road rationing scheme as Assembly polls are approaching.

Senior BJP leader and Rajya Sabha MP Vijay Goel said if the Kejriwal government thinks stubble burning is the main reason for harmful air quality in Delhi then why did it resort to the odd-even scheme.

The Delhi government will take a final call on Monday whether or not to extend the scheme, which was implemented from November 4-15, considering the current situation of air pollution.

A Central Pollution Control Board (CPCB) led task force on pollution lifted the ban on the operation of non-PNG industries in Delhi and coal-based units in NCR as the air quality in the region improved on Saturday and is expected to become better in the next two days.

An India Meteorological Department officer has said the wind direction is north westerly and surface wind speed is high.

Favourable weather is likely until November 18 and thereafter, the AQI may enter the higher end of 'poor' category or lower end of 'very poor' category.