China Coast Guard expelled four Philippine vessels that illegally entered the waters near the Ren'ai Reef on Saturday in accordance with the law, a spokesman said on Sunday.

Gan Yu, spokesman for China Coast Guard, said in a brief statement that without the approval of the Chinese government, two Philippine supply vessels and two Philippine coast guard vessels illegally entered waters adjacent to the Ren'ai Reef of China's Nansha Islands on Saturday.

The Chinese coast guard conducted "necessary control" in accordance with the law and prevented the Philippine ships carrying "illegal construction materials", he said.

The spokesman urged the Philippines to immediately stop its infringing activities in the waters, stressing that China has indisputable sovereignty over the Nansha Islands and their adjacent waters, including the Ren'ai Reef.

China Coast Guard will continuously carry out rights protection and law enforcement activities in the waters under China's jurisdiction in accordance with law, Gan added.