Unprecedented air pollution levels in Pakistan's second-largest city of Lahore prompted authorities to take emergency measures on Sunday, including issuing work-from-home mandates and closing primary schools.

The city held the top spot on a real-time list of the world's most polluted cities on Sunday after recording its highest ever pollution reading of 1900 near the Pakistan-India border on Saturday, based on data released by the provincial government and Swiss group IQAir.

The government has shut primary schools for a week, advising parents to ensure children wear masks, said Senior Minister of Punjab Marriyum Aurangzeb during a press conference, as a thick blanket of smog enveloped the city.

Citizens have been urged to stay indoors, keep doors and windows shut, and avoid unnecessary travel, she said, adding that hospitals had been given smog counters.

To reduce vehicle pollution, 50% of office employees would work from home, said Aurangzeb.

The government has also imposed a ban on three-wheelers known as rickshaws and halted construction in certain areas to reduce the pollution levels. Factories and construction sites failing to comply with these regulations could be shut down, she said.

Aurangzeb described the situation as "unexpected" and attributed the deterioration in air quality to winds carrying pollution from neighboring India.

"This cannot be solved without talks with India," she said, adding the provincial government would initiate talks with its bigger neighbor through Pakistan's foreign ministry.

The smog crisis in Lahore, similar to the situation in India's capital Delhi, tends to worsen during cooler months due to temperature inversion trapping pollution closer to the ground.