BEIJING - China's top economic planner confirmed on Tuesday that it has approved seven provincial regions to start a pilot greenhouse gas emission rights trading scheme in an effort to encourage carbon emission reductions.

The municipalities and provinces involved are Beijing, Tianjin, Shanghai, Chongqing, Shenzhen, Hubei and Guangdong, an official with the National Development and Reform Commission told Xinhua under the condition of anonymity.

However, the official refused to elaborate on the pilot scheme. Details such as how it will work and how long it will last are not available.

According to a statement posted on the official website of the Chongqing municipal government (www.cq.gov.cn), the pilot is an important means to realize China's emission reduction targets, while minimizing costs.

The country has pledged to reduce carbon dioxide emissions per unit of GDP by 40 to 45 percent by 2020 compared with 2005 levels.

According to a white paper China issued on Tuesday, the government will prioritize global climate change during its 12th Five-Year Plan period (2011-2015).