Schools, universities and government offices in the Iranian capital will be closed on Saturday for the second time in a month due to high air pollution, Tehran governor Morteza Tamadon said Thursday, according to AFP. 

Emergency services also advised residents to avoid unnecessary travel in the city, the ISNA news agency reported.

Tamadon said a pollution committee took the decision after smog failed to dissipate over the past three days, the Mehr news agency reported.

“Closure is not the solution but it is the best decision, considering the prolonged high level of pollution indicators,” he said, adding that current level of pollution was expected to last another three days.

Only emergency and health services would report for work, he added.

A similar measure was taken on December 3 when air pollution covered Tehran, prompting former health minister Marzieh Vahid Dastjerdi to urge residents to leave the city.

On Thursday, vice president for environmental protection Mohammad Javad Mohammadizadeh told state television that traffic restrictions would also be applied.

Tamadon said all sports activities would also be suspended until early next week.

The pollution, which is blamed mainly on bumper-to-bumper traffic, is a constant woe for the eight million residents of a city wedged between two mountains, which trap fumes over Tehran, AFP reported.

Western sanctions on fuel imports have also forced Iran to rely on domestic production of petrol of a lower grade, which results in more pollution.

Efforts by officials to boost public transportation, including extending the metro and establishing lanes for buses only, have barely dented the problem because of the growing number of cars, many of which are old and inefficient, according to AFP.