Bonfires lit by residents as part of the Pongal festival in the presence of high humidity, low temperature and moisture may cause smog which disrupts visibility.
The government has pledged millions of dollars and deployed extra teams to improve enforcement of existing environmental laws that include banning farmers from burning their fields.
Visibility on the roads of Delhi, were considerably low and is expected to get worse at night.
The air quality index in Beijing climbed to 213, which is categorised by the World Health Organisation, (WHO) as "very unhealthy".
Vehicular emissions, as well as illegal crop burning in the farm states surrounding New Delhi, have caused air quality to deteriorate dramatically, prompting calls for tough action.
SC to hear fresh plea today to curb rising pollution in Delhi-NCR; NGT says no review plea on odd-even scheme filed
The fresh plea seeks direction to the Centre and the states concerned to take measures on curbing road dust and stubble burning.
At least 69 trains were delayed, 22 rescheduled and eight trains were cancelled due to the shallow fog in northern India.
After a relative respite on Saturday, the national capital was enveloped in a thick blanket of smog on Sunday due to high levels of humidity.
According to a MeT department official, the minimum temperature fell to 13 degree Celcius, one degree below the season’s average. The weatherman also predicted the rain on November 14 or 15.
Dense smog continued to enshroud Delhi and the National Capital Region on Sunday, with pollution level remaining in the ‘severe’ category.
NGT gives green signal to Delhi's odd-even scheme to curb air pollution; no exemptions to VVIPs, women
No exemption will be granted to women, two-wheelers or VVIPs, announced a bench headed by NGT chairperson Justice Swatanter Kumar.
Meanwhile, 64 trains are running late, 14 rescheduled and two have been cancelled in view of the thick smog hung over the city.
Chandigarh Pollution Control Committee's member secretary P J S Dadwal said this is the first time that Chandigarh has pollution of such levels.
According to the department, 10-year-old diesel vehicles and 15-year-old petrol vehicles will be seized in the NCR districts.
The Aam Aadmi Party said the smog in Delhi is not due to stubble burning in Punjab, but is being caused by industrial and vehicle pollution.