Record-high air pollution in Pakistan’s Punjab province has prompted authorities to close more schools and keep government employees at home, as doctors reported an increase in people seeking treatment for smog-related ailments.

Marriyum Aurangzeb, a senior minister in the Punjab province, urged residents to voluntarily wear face masks and avoid unnecessary travel, and said that “otherwise, the government will be forced into a complete lockdown”.

Lahore, the provincial capital of 14 million people and Pakistan’s cultural hub, remained the world’s most polluted city on Wednesday with Air Quality Index readings of more than 1,100.

Anything over 300 is considered hazardous to health.

Smog in Pakistan
Motorcyclists as smog envelops the city (KM Chaudary/AP)

Authorities earlier in the week shut down schools in Lahore, and on Wednesday they closed schools in 18 surrounding districts.

Ms Aurangzeb said 50% of government employees in Lahore had been told to work from home until next week.

Hospitals and private clinics have been treating patients complaining of coughs or burning eyes.

“Tens of thousands of patients suffering from respiratory diseases were treated at hospitals and clinics in a week,” said Salman Kazmi, vice president of the Pakistan Medical Association.

He said people can be seen coughing everywher in Lahore, but people are still not wearing face masks to protect themselves from the pollution.

Authorities in the city have already banned barbecuing food without filters, as well as the use of motorised rickshaws — and wedding halls must close by 10pm.

The government said it was also looking into methods to induce artificial rainfall to combat the pollution.