The Philippines has summoned China's ambassador in Manila after two Chinese ships blocked a Philippine Navy vessel from arresting Chinese fishermen in the South China Sea.
Eight Chinese fishing vessels were anchored off Scarborough Shoal, the Philippine government said on Wednesday, as Albert del Rosario, the country's foreign affairs secretary, called in Ma Keqing, the ambassador, for talks.
Manila and Beijing contest sovereignty over the small group of islands and reefs, which lie about 124 nautical miles from the western coast of the Philippines' main island of Luzon.
The foreign affairs department statement said the Philippines' flagship warship, the Gregorio Del Pilar, found the eight vessels there on Sunday while patrolling the area.
Two "Chinese maritime surveillance ships" then sailed to the shoal on Tuesday, the statement said.
The ships placed themselves between the Gregorio del Pilar and the fishing vessels, "thus preventing the arrest of the erring Chinese fishermen", the statement said. "The situation has remained unchanged as of this morning," it added.
Del Rosario had contacted Ma to emphasise that the area was "an integral part of Philippine territory" and invite him for talks aimed at finding a diplomatic solution, according to the statement.
Zhang Hua, a spokesman for China's embassy in Manila, told AFP on Wednesday he had no comment on the latest standoff.
The incident is the latest flare-up in tensions between the two countries over competing territorial claims to parts of the South China Sea, which is believed to sit atop vast oil and gas deposits.
China insists it has sovereign rights to all of the South China Sea, even waters close to the coast of other countries and hundreds of miles from its own mainland.
The Philippines says it has sovereign rights over waters within its 200-nautical-mile exclusive economic zone, and that its position is supported by international law.
Apart from China and the Philippines, Taiwan, Malaysia, Brunei and Vietnam, also have overlapping claims to parts of the South China Sea, making the waters one of Asia's potential flashpoints for armed conflict.
The Philippines and Vietnam complained last year of increasingly aggressive acts by China in staking its claim to the South China Sea.
The Philippines accused Chinese vessels of firing warning shots at Filipino fishermen, as well as harassing an oil exploration vessel.