India said on Sunday that it would tighten restrictions including on construction activities and vehicle movements in New Delhi and surrounding areas from Monday to combat worsening air quality.

The new measures, effective from Monday morning, entail a ban on diesel trucks in Delhi, the closure of educational institutions and a shift to remote working, as advised by the local administration.

Local authorities have also announced plans to sprinkle water with dust suppressants on roads and deploy mechanised sweeping to reduce dust.

“Continuing unfavourable meteorological conditions, with low wind speed are the major causes for sudden spike in AQI (Air Quality Index),” said a government statement following an emergency meeting of a panel of state officials.

The panel, which presented an eight-point action plan, has urged the public, particularly children, senior citizens and those with respiratory, cardiovascular, cerebrovascular or other chronic diseases, to stay indoors.

Air quality in northern India has worsened over the past week, with New Delhi’s AQI recording a reading of 465, classified as “severe plus category”, on Sunday evening due to unfavourable meteorological conditions, a government statement said.

Around 38 per cent 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.

New Delhi grapples with smog, a toxic blend of smoke and fog, each winter as cold air traps dust, emissions and smoke from illegal farm fires.

Officials blamed high pollution, combined with humidity, calm winds and dropping temperatures for the smog, with the Indian meteorological department forecasting smog conditions and low wind speeds until Saturday.

The city’s minimum temperature is expected to drop to 14° Celsius on Monday, down from 15.9°C the previous day, weather officials said.