BEIJING/TAIPEI, Oct 20 - China's military said on Tuesday it had sent forces to watch a US warship that "illegally" entered waters around a disputed shoal in the South China Sea, while further north in the waterway, Taiwan reported a standoff with a Chinese vessel.
China views almost all of the South China Sea as its own territory, despite overlapping claims by Brunei, Malaysia, the Philippines, Taiwan and Vietnam, with recent tension most pronounced between Beijing and Manila.
The Chinese military's Southern Theatre Command said the USS Charleston "illegally intruded" into waters adjacent to Sabina Shoal in the Spratly Islands without Chinese government approval in the early hours of Tuesday.
"The US action infringes upon China's sovereign rights and interests, jeopardises maritime security, and is detrimental to regional peace and stability," it said in a statement.
"The US side should immediately cease such activities."
China's navy dispatched forces to track and monitor the ship, it added.
A US Nay 7th Fleet spokesperson said the USS Charleston conducted routine operations in international waters consistent with international law.
"All nations enjoy freedom of navigation and other lawful uses of the sea in this area," the spokesperson said in a statement. "The United States will continue to fly, sail, and operate wherever international law allows in support of regional peace, stability, and security."
A Philippines' military spokesperson said the US ship "did not trespass into 'Chinese territory'," adding that no nation had the authority to require prior permission for "lawful transit through international waters."
Last month, a China Coast Guard vessel rammed a Philippine boat on a refuelling mission near the same shoal, according to the Philippine Coast Guard. China blamed the collision on the Philippine side.
China and the Philippines, which has a mutual defence treaty with the US, both contest sovereignty over Sabina Shoal and the entire Spratly Islands archipelago.
PRATAS STANDOFF
In a separate incident on Tuesday at the top end of the South China Sea, Taiwan's Coast Guard said a Chinese Coast Guard ship had entered restricted waters near the Taiwan-controlled Pratas Islands.
The Taiwan Coast Guard said its ship the "Taichung" was dispatched to warn away the Chinese boat, while both sides broadcast messages to each other.
The Chinese ship broadcast that "the so-called Republic of China does not exist", referring to Taiwan's official name, while the Taiwanese ship broadcast back that "the Republic of China, Taiwan, is a sovereign and independent country", Taiwan's Coast Guard said, adding the standoff was continuing.
China's Taiwan Affairs Office did not immediately respond to a request for comment.
The office said last week that Taiwan must "bear the consequences" of its Coast Guard using a water cannon against a Chinese fishing boat near the Pratas.
The Pratas Islands lie roughly between southern Taiwan and Hong Kong, but are only lightly defended and security is the responsibility of Taiwan's Coast Guard.
China has also been stepping up coast guard activity around Taiwan, including off the island's east coast, causing concern in Western capitals.
China views democratically governed Taiwan as its own territory.
Speaking at a forum in Taipei on Tuesday, the chair of a review commission appointed by the US Congress said Chinese coast guard patrols to the east of Taiwan were "highly destabilising".
Addressing the same event, Taiwan's National Security Council Secretary-General Joseph Wu said China had no legal claim to the waters off the island's east.
(Reporting by Liz Lee and Ben Blanchard; Additional reporting by Karen Lema in Manila; Editing by Christopher Cushing, Clarence Fernandez, Lincoln Feast and Kate Mayberry)
