BEIJING -- The Ministry of Environmental Protection said on Monday that it will mark out China's ecologically sensitive and vulnerable areas and functional zones before the end of next year.

The ministry said in a statement that it has completed the demarcation of the ecological "red line" in Inner Mongolia, Jiangxi, Guangxi and Hubei.

A guideline was also issued to clarify the range for the demarcation, procedures and requirements.

The demarcation will be completed by the ministry's Nanjing Institute of Environmental Sciences, Chinese Research Academy of Environmental Sciences, Chinese Academy of Sciences and Peking University.

The area of ecologically vulnerable zones in key regions, such as Inner Mongolia Autonomous Region which is dominated by grasslands and deserts, should be no less than 20 percent of its total area, said the statement.

The government will announce policies and regulations regarding the management of ecological zones in 2014 to define obligations of various levels of governments, communities and individuals in protecting ecological "red-line" areas, it said.

"The severest controlling system will be adopted" in order to closely observe the bottom line, safeguard the country's ecological security, and promote the sustainable development of the economy and society, the statement said.