Pakistani officials say dangerously poor air quality has forced the provincial government in Lahore to close primary schools for a week.

Pakistan's province of Punjab set up a "smog war room" to tackle severe pollution, officials said, as poor air quality turned its capital of Lahore into the world's most polluted city and forced the closure of some educational institutions.

Dangerously poor air quality forced Pakistani authorities in the cultural capital of Lahore to close primary schools for a week, government officials said, after the air quality index hit a record high over the weekend.