Full coverage: South China Sea Is Indisputable Part of China

US Defense Secretary Ash Carter also alleged that China is isolating itself in the ways it tackles the South China Sea issue.

Guan Youfei, director of the Foreign Affairs Office of China's National Defense Ministry, denounced Carter's comments as "groundless".

He said the allegations weren't true and that the US aims to isolate China. He added that China plays an active role in UN peacekeeping and oceanic escort missions and is not isolated. He also pointed out an increase in military exchange and cooperation between China and the US. He said China is ready to maintain regional security and urged the US to abandon a Cold War mentality.