China says U.S. Navy patrols in the South China Sea require it to increase the defense capabilities of the islands it controls in the area.

The Chinese Defense Ministry has condemned Tuesday's latest sail-by by the U.S. Navy to reinforce its position that China's new man-made islands in the strategically vital water body do not enjoy the legal rights of natural islands.

The destroyer USS William P. Lawrence passed within 12 nautical miles (22 kilometers) of Fiery Cross Reef, the limit of what international law regards as an island's territorial sea. The reef is now an island with an airstrip, harbor and burgeoning above-ground infrastructure.

Chinese authorities monitored and issued warnings to the U.S. destroyer as it passed. The ministry said in a statement that it may also boost patrols.