By Rosemarie Francisco
MANILA (Reuters) - China and the Philippines deployed on Thursday ships to a disputed area of the South China Sea as a standoff simmered despite efforts by both sides to resolve the disagreement diplomatically.
China has territorial disputes with several countries in the region, including the Philippines, over areas of the South China Sea, which is believed to be rich in oil and gas and is crossed by important shipping lanes.
China has sought to resolve the disputes on a one-on-one basis but there is concern among its neighbors over what some see as its growing assertiveness in staking its claims over the sea and various islands, reefs and shoals.
Philippine Foreign Affairs Secretary Albert del Rosario said a third Chinese vessel had arrived at the Scarborough Shoal, a small group of rocky outcrops.
"Some time today, this morning," Del Rosario told reporters when asked when the Chinese ship had arrived.
"It's a bureau of fisheries Chinese civilian ship," he said.
Both sides traded diplomatic protests on Wednesday over the dispute in an area straddling shipping lanes between East Asia and Europe and the Middle East, with China alleging harassment by the Philippine navy of its fishermen and Manila complaining of illegal fishing.
Manila sent a coastguard cutter to the shoal on Thursday to reinforce its largest warship, a U.S. Hamilton-class cutter, which on Sunday found some Chinese fishing boats anchored in the area, with one carrying illegally collected corals, giant clams, and live sharks.
Del Rosario said he had raised the matter with China's ambassador, Ma Keqing, adding he was not alarmed by the arrival of the third Chinese ship and the talks would go on.
"We're moving forward but it's still work in progress," he said.
Chinese Foreign Ministry spokesman Liu Weimin told a daily briefing in Beijing that he did not know how many Chinese vessels were in the area.
"What I can tell you is that China's law enforcement vessels are currently protecting the safety of fishermen and their boats in these seas," said Liu, adding that the vessels were protecting the "legitimate" activities of Chinese fishermen.
The Philippines refers to the disputed area as the Panatag Shoal while China calls it Huangyan Island.
Philippine officials said the navy vessel was likely to leave the area soon, as part of Manila's effort to ease tension as it had said the navy should not be involved in the enforcement of the country's maritime laws.
The shoal is about 125 nautical miles off the main Philippine island of Luzon and near Subic Bay, which once housed the largest U.S. base outside its mainland.
In March last year, Chinese navy ships threatened to ram a Philippine survey vessel in another disputed area, the Reed Bank. In response, the Philippines scrambled aircraft and ships.
That incident prompted the Philippines to seek closer ties with its main ally, the United States, offering it greater access to air fields and military facilities.
Asked if the Philippines had sought the U.S. help with the latest dispute, a foreign affairs spokesman said: "It is not appropriate at this time to seek help from other countries."
Philippine and U.S. forces are due to hold a military exercise near the Reed Bank this month.
Vietnam, Brunei, Malaysia and Taiwan also have claims in the South China Sea that China disputes.
(Addtional reporting by Bejing bureau; Editing by Robert Birsel)