India's capital city of Delhi has virtually shut down as air pollution hit "severe plus" levels, according to Indian government officials in its pollution control authority.

Air pollution chokes New Delhi every winter, but this year's smog has already derailed everything from transport and road work to schools.

In several areas of the city, pollution levels were more than 50 times higher than the World Health Organization’s recommended safe limit. Forecasts say the poor air quality will continue into the week.

Residents in India's northern states woke up to another day of poor air quality on Tuesday, as a layer of dense fog shrouded most of the region, and pollution in the capital Delhi remained severe.

Around 38% of the pollution in New Delhi this year has been caused by stubble burning - a practice where stubble left after harvesting rice is burnt to clear fields - in the neighbouring states of Punjab and Haryana, according to SAFAR, a weather forecasting agency under the ministry of earth sciences.

Despite the recurrence of extreme pollution episodes and their very high health costs, the authorities are not taking any structural measures.

Delhi's new action plan to combat rising pollution includes a ban on non-essential trucks, school closures, and remote work.