Beijing announced Monday its troops will operate from Sansha in the Paracel Islands, one of two archipelagos in the South China Sea that are claimed by both China and Vietnam. The move is likely to stoke further tensions in the region.

"The decision by China's Central Military Commission to deploy troops to islands in the South China Sea, which are also claimed by Vietnam, is unnecessarily provocative," the Republican McCain said in a statement.

He said other action by China including its appointment of legislators to govern such disputes "only reinforces why many Asian countries are increasingly concerned about China's expansive territorial claims, which have no basis in international law, and the possibility that China will attempt to impose those claims through intimidation and coercion."

The actions by Beijing "are disappointing and not befitting a responsible great power," he said.

"We must continue to urge all parties with territorial claims in the South China Sea to seek a peaceful, multilateral resolution that is based on international law."

Beijing did not say when the garrison would be established.

Disputes have flared in recent weeks, with Vietnam and the Philippines criticizing what they call Chinese encroachment.

The foreign department said it summoned Ma Keqing to lodge the complaint, and also to object to the arrival of a military-escorted Chinese fishing fleet near the contested Spratly Islands.

The Chinese defence ministry announced plans to operate troops from Chinese-held Sansha or Woody Island in the Paracels on Monday, a month after Beijing designated the island as China's administrative centre for both the Paracel and Spratly groups.

While the Philippines does not have territorial claims on the Paracels, foreign department spokesman Raul Hernandez said the Chinese plan to administer both island groups from Sansha was unacceptable.

"The Philippine government has expressed its grave concern and registered its strong protest over the Chinese government decision to establish a military garrison in Woody Reef," Hernandez told reporters.

China claims sovereignty over nearly all of the South China Sea, which is believed to hold vast amounts of oil and gas, while the Philippines, Taiwan, Brunei, Malaysia and Vietnam each claim portions.

Disputes have flared in recent weeks, with Vietnam and the Philippines criticising what they call Chinese encroachment.

China and South Vietnam once administered different parts of the Paracels but after a brief conflict in 1974, Beijing took control of the islands.

The Philippine foreign department said it summoned the Chinese ambassador over the garrison plans as well as to receive a strong objection to China's dispatch of a military-backed fishing fleet in Spratly waters.

The Filipino coast guard monitored a fleet of 29 fishing vessels, a cargo vessel, and three other ships including one Chinese navy vessel near Fiery Cross Reef and Subi Reef on July 18, Hernandez said.

"The use of armed government vessels to escort fishing vessels that conduct non-fishing activities is a violation of Philippine territory and a violation of obligation of states under international law," Hernandez said.