China urged on Tuesday the Philippines to make more helpful efforts to ease tensions over Huangyan Island and promote bilateral ties between the two nations.
The head of US forces in the Pacific on Monday reaffirmed the US' commitment to support the Philippines amid continuing maritime disputes between Manila and Beijing.
US Secretary of State Hillary Clinton arrived in Vietnam's capital of Hanoi on Tuesday for a two-day visit expected to further boost bilateral ties.
China on Tuesday urged the Philippines to act in a manner that contributes to regional stability.
Washington and Manila kicked off their second joint military drill of the year, and analysts warned that the move will bring more uncertainty to regional ties.
Philippine security forces alleged that a Muslim rebel commander was behind Monday's abduction of two Chinese businessmen in southern Philippines.
Philippine Navy forces will commence a set of training activities on Sunday.
Despite China's low-key restraint, offer of mutually beneficial economic cooperation, diplomatic protests and consultation within ASEAN, the Philippines insists on provoking China.
On April 10, China and the Philippines became embroiled in a standoff in disputed waters in the South China Sea. China has shown restraint in handling the incident. But the messages sent by the Philippine government and media have been provoking and its actions, such as urging other countries to 'take a stand' and extending the dispute to the entire South China Sea, have only intensified the situation.
The Philippines argued that Huangyan Island was its "inherent territory" because the island was in its 200-nautical-mile Exclusive Economic Zone.
The Scarborough Shoal does belong to China which discovered it and drew it in a map as early as 1279 during the Yuan Dynasty.