China repeats call for implementing DOC BEIJING, May 22 (Xinhua) -- China on Wednesday urged relevant countries to fully and earnestly implement the Declaration on the Conduct of Parties in the South China Sea (DOC) and refrain from actions that could amplify or complicate the issue. Chinese Foreign Ministry spokesman Hong Lei made the remarks at a regular press briefing in response to a media request for a comment on the Philippines' recent protest. According to a spokesman for the Department of Foreign Affairs of the Philippines, the Philippines recently filed a protest against a Chinese warship and marine surveillance ships that sailed to the waters around Ren'ai Jiao, referred to as "Ayungin Shoal" by the Philippines. Noting that Ren'ai Jiao is part of the Nansha Islands, and that China has indisputable sovereignty over the Nansha Islands and their adjacent waters, Hong said Chinese public service vessels are entitled to patrol there. Hong also urged concerned parties to refrain from any actions that could undermine peace and stability in the region.