China announced Saturday it has completed drawing ecological protection red lines nationwide to identify the country's crucial ecological zones and enforce strict protection in those areas.

No less than 3.15 million square km of area across China, including no less than 3 million square km of land area, or over 30 percent of the country's total land area, and no less than 150,000 square km of sea area, has been demarcated within the red lines, according to the Ministry of Natural Resources.

The red lines cover areas that are critical in environmental function, ecologically sensitive and vulnerable, and vital for biodiversity.