Philippine President Benigno Aquino has begun a five-day state visit to China aimed at securing multi-billion-dollar trade agreements while facing bitter disagreements with Beijing over territorial claims in the South China Sea.

Mr. Aquino arrived in Beijing Tuesday, leading a delegation of about 300 Philippine business leaders and prepared to witness deals aimed at boosting trade six-fold in the next five years to more than $50 billion. The official Xinhua news agency said the Philippine leader will hold a series of meetings with President Hu Jintao and Premier Wen Jiabao.

Ahead of his visit, Mr. Aquino told Chinese journalists that both Manila and Beijing want to use international law to resolve disputes over competing claims to potentially energy-rich territories in the South China Sea. In his comments, published Sunday, he compared the dispute, which Manila says has included at least seven maritime confrontations, to “a test that makes for a stronger relationship.”

China, the Philippines, Vietnam, Taiwan, Malaysia and Brunei lay claim to all or part of the South China Sea, including the vast, uninhabited Spratly Island archipelago. The area is thought to hold large deposits of oil and natural gas, and is home to one of the world's busiest international shipping lanes.

China claims sovereignty over the entire sea, based on an early 20th century map.

The Philippines counters the Chinese claims by referring to the United Nations Convention on the Law of the Seas. The convention grants nations more than a 300-kilometer exclusive economic zone beyond their coastlines.