Smogy, scary days are set to return in Delhi as rain has ended and it's time for crop burning season in North India, especially in the adjoining states of the national capital.

While some regions across Delhi-NCR saw an improvement in the air quality from "severe plus or emergency" to "severe" on Saturday, the national capital continues inhaling toxins with no respite likely for at least a week, officials and experts said.

Six trains were cancelled as it was a partly cloudy Friday morning in the national capital with the minimum temperature recorded at 13.9 degrees Celsius, a notch above the season's average.

Uttar Pradesh Chief Minister Yogi Adityanath on Thursday gave strict directives to municipal corporations to tackle the problem of smog as soon as possible.

Over half of Delhi's college students were suffering from respiratory problems during smog week, a survey has found.

Delhi Chief Minister Arvind Kejriwal on Wednesday met Haryana Chief Minister Manohar Lal Khattar here to discuss the issues of stubble burning and air pollution.

The National Green Tribunal (NGT) on Tuesday turned down the Delhi government's plea to exempt women drivers and two-wheelers from the odd-even vehicle rationing scheme.

The toxicity in the air rose to "severe-plus" category on a day schools in the national capital reopened after remaining closed since Thursday due to "severe" air pollution levels.

Delhi Chief Minister Arvind Kejriwal re-tweeted posts by media houses saying the odd-even will kick in from November 13. Government officials said that modalities of the road rationing scheme are being worked out.

Air pollution remained severe on Wednesday and there are no chances of it improving on Thursday either, said Central Pollution Control Board (CPCB).