Image caption The Philippines' largest warship is in a stand-off with Chinese vessels in the South China Sea

The Philippines says it has withdrawn its largest warship from a continuing stand-off with Chinese boats in the disputed South China Sea.

Earlier on Thursday a Philippine coastguard vessel arrived in the area, known as the Scarborough Shoal.

The Philippines also says China has sent a third ship to the scene.

The Philippine foreign minister said negotiations with China would continue. Both claim the shoal off the Philippines' north-west coast.

The Philippines said its warship found eight Chinese fishing vessels at the shoal when it was patrolling the area on Sunday.

It did not say why the warship had been pulled back. "That is an operational undertaking I can't discuss with you," Foreign Affairs Secretary Albert del Rosario was quoted by AFP news agency as saying.

"We are pursuing the diplomatic track in terms of coming to a resolution on the issue," Mr Del Rosario said.

Differing views

In a statement , the Philippines said that its navy boarded the Chinese fishing vessels on Tuesday and found a large amount of illegally-caught fish and coral.

Two Chinese surveillance ships then apparently arrived in the area, placing themselves between the warship and the fishing vessels, preventing the navy from making arrests.

The Philippines summoned Chinese ambassador Ma Keqing on Wednesday to lodge a protest over the incident. However, China maintained it had sovereign rights over the area and asked that the Philippine warship leave the waters.

China's state-run newspaper China Daily claimed in an editorial that the Chinese fishermen were "harassed" by the Philippine ship.

"China should take more measures to safeguard its maritime territory," the newspaper stated.

"The latest moves by China's two neighbours are beyond tolerance," it added, also referring to Vietnam. "They are blatant challenges to China's territorial integrity."

However, the Global Times newspaper added that China "has the patience to work out solutions with the countries concerned through negotiation".

The stand-off comes as the Philippines prepares for joint naval exercises with the United States from the 16 to 27 April near the disputed area.

Six countries claim competing sovereignty over areas in the South China Sea, which is believed to contain huge deposits of oil and gas.

Along with China and the Philippines, they are Brunei, Malaysia, Vietnam and Taiwan.

China's claim includes almost the entire South China Sea, well into what the UN Convention on the Law of the Sea recognises as the 200-mile-from-shore Exclusive Economic Zones of other claimants.

That has led to occasional flare-ups and to competition to occupy islands, reefs and sandbars.