The official map of China, which previously included an inset to reflect its South China Sea territories, has been extended vertically to include the country's maritime areas in the main cartography.

The South China Sea territories are based on the country's nine-dash line, which covers the Xisha, Zhongsha and Nansha island groups and surrounding waters of more than 2 million square kilometers.

"The new map gives readers a direct impression about the country's territories," Lei Yixun, chief editor of Hunan Maps Press, the publisher, told Xinhua News Agency on Tuesday.