Chinese Vice Premier Zhang Gaoli ordered a temporary shutdown of factories to ensure air quality during a meeting of Asia-Pacific leaders in Beijing next month, the official Xinhua news agency reported late on Friday.

It is the strongest measure yet to curb pollution for the Nov. 7-11 meeting in the capital, which has been enveloped by heavy smog over the past few days.

Zhang told officials that ensuring air quality during APEC is the "priority of priorities", although the task will be a "tremendous pressure and challenge" given dropping temperatures and the start of the coal burning season in northern China, Xinhua said.

Zhang also said vehicle controls must be strictly enforced and residents should be encouraged to take public transportation during the meeting, the report said.

In an effort to ease traffic congestion and curb pollution, Beijing has already announced that public workers in the capital will be given six days off during the APEC meeting.