ISLAMABAD: Pakistan’s biggest city Karachi topped the daily ranking of most polluted city in the world, leaving authorities helpless to curb pollution, reported German news agency (dpa).

The air quality of the port city was recorded as 227, making it the most polluted city in the world on Sunday, according to IQAir, a global environmental think tank.

Meanwhile, the country’s second largest city Lahore stood at number three in the list of most polluted cities.

The provincial government of Punjab made it mandatory for citizens in 10 smog-hit districts to wear face masks for one week.

“Prioritising health is our collective responsibility. Please adhere to the guidelines for a safer community,” Punjab Chief Minister Mohsin Naqvi wrote on X, the platform formerly known as Twitter.

On Saturday, a “smart lockdown” was imposed in the affected districts to tackle the escalating air pollution levels by reducing industrial and transport-related emissions. Educational institutions and offices remained closed.

White smog has engulfed at least 10 districts of the central Punjab province, including the provincial capital Lahore, home to more than 11 million people.

Pakistani authorities blame industrial emissions, smoke from brick kilns and vehicles, the burning of crop residue and general waste as causing air pollution and smog in Lahore.

Pakistan is responsible for less than one per cent of global carbon emissions but is among the top 10 most climate-vulnerable nations.–Bernama-dpa