The Philippines has withdrawn its biggest warship from a disputed area in the South China Sea, in an apparent attempt to lessen tensions with China over a naval standoff in the disputed waters.

Foreign Affairs Secretary Albert del Rosario said Thursday that a smaller coast guard boat will replace the warship at the Scarborough Shoal, located about 230 kilometers off the northwestern Philippines.

The standoff began Tuesday when two Chinese surveillance vessels blocked the Philippines warship, the U.S.-built Gregorio del Pilar, from arresting a group of Chinese fishermen there.

Both sides say they prefer a diplomatic solution to the crisis. But Philippine officials say China sent a third vessel, a boat from Beijing's fishing bureau, to the region on Thursday, as Beijing appeared to harden its resolve.

Chinese foreign ministry spokesperson Liu Weimin said his government is committed to protecting its sovereign right to the group of islands, which are known as Panatag in the Philippines, and as Huangyan Island in China.

“I am not so clear on the specifics in the waters of Huangyan Island, but I can tell you that our law enforcement ships are in the water of Huangyan Island to protect the safety of the Chinese fishermen and protect their legitimate activities in these waters.”

China's Communist Party-affiliated Global Times newspaper said Thursday that Beijing will continue to strive for peace and stability, but warned it will not make “unprincipled concessions to the recklessness of other countries.” The editorial also accused the U.S. of worsening the situation by encouraging the Philippines and Vietnam to “take more risks.” It did not elaborate.

The Philippines says it first noticed the Chinese fishing boats on Sunday. When Philippine authorities confronted the fishermen on Tuesday, Manila says the two Chinese surveillance ships positioned themselves between the warship and the Chinese fishing boats, “preventing the arrest of the erring fishermen.”

China says the fishing boats were simply taking shelter near the island due to inclement weather. It said the two surveillance ships were taking action to safeguard “Chinese national maritime interests and rights.”

Tensions in the region have risen in recent years as China becomes increasingly assertive about its claims over the entire 3.5 million-square-kilometer South China Sea, which is thought to be rich in oil and gas.

There has been a series of run-ins involving fishermen, military patrols, and other vessels in the disputed waterway, parts of which are also claimed by Vietnam, Malaysia, Brunei and Taiwan.

This week's dispute between the Philippines and China is the most dangerous confrontation between the two sides in recent years, and comes just after the countries said they had been working to lower tensions over the contested territory.