Director of the State Environmental Protection Administration Xie Zhenhua said Friday that in the coming few years China will implement an overall volume control and a license system for waste emission, on the basis of which, trading of sulfur dioxide will be carried out in some key areas.

In response to questions at a news conference, Xie said that China and the United States have had cooperation in the trading of sulfur dioxide emission, and pilot projects in some places and enterprises have been doing well. The key to trading waste emission is the implementation of overall volume control and license system.

He said that the policy of waste emission trading has been widely accepted, and the policy is expected to spread further following the success of the pilot projects.