MANILA, Philippines >> The Philippines’ top diplomat said Thursday that China has been rushing construction projects, including massive land reclamation, in the disputed South China Sea in hopes of forestalling any legal moves against its vast territorial claims.

Foreign Secretary Albert del Rosario said the Chinese construction is aimed at bolstering its claims to virtually the entire South China Sea. He called Beijing’s claims “invalid and excessive and in violation of international law.”

The Philippines and other governments which have territorial disputes with Beijing in the busy sea have been particularly concerned by massive Chinese land reclamation projects that have turned a number of previously submerged reefs in the Spratlys archipelago into artificial islands with buildings, runways and wharves.

Alarmed by what it describes as increasing Chinese assertiveness, the Philippines sought international arbitration two years ago to challenge the legality of Beijing’s claims.

China has ignored the Philippine legal challenge but a U.N.-backed tribunal in The Hague may hand down a ruling as early as next January or February, del Rosario said.

There also have been proposals for China and Southeast Asian nations to conclude a legally binding “code of conduct” restricting aggressive behavior that could spark armed confrontations in the disputed areas, which straddle some of the world’s busiest sea lanes and are believed to have rich undersea oil and gas deposits.

“It is clear to us that China is accelerating its expansionist agenda and changing the status quo to … control nearly the entire South China Sea before the conclusion of the code of conduct and the handing down of a decision of the arbitral tribunal,” del Rosario said.

The Philippines has expressed concern that Beijing could transform its newly created islands into military logistical and resupply hubs to bolster its territorial claims and pose a more serious challenge to rival claimants.

The Philippines has protested the reclamation projects. The Chinese Embassy did not immediately respond to Rosario’s comments, but in the past Beijing has asserted its right to undertake any activity in territories it claims.

U.S. Sen. John McCain and three other top-ranking senators overseeing U.S. defense and foreign policy called last week for a comprehensive strategy to deal with China’s territorial moves, including land reclamation and construction in disputed areas, warning that “longstanding interests of the United States, as well as our allies and partners, stand at considerable risk.”