SUBIC, Philippines — The Philippines on Tuesday celebrated the arrival of a decommissioned US Coast Guard cutter as its second major warship to challenge China's massive territorial claims that Filipino officials say have intruded into their country's potentially oil-rich offshore seas. President Benigno Aquino III saluted as the 3,250-ton white cutter, renamed Philippine navy frigate BRP Ramon Alcaraz, docked at a wharf in Subic Bay freeport northwest of Manila. A part of the former US naval base will soon be turned into a Philippine military hub after the government approved a plan to shift its assets closer to the disputed islands in the South China Sea. A military brass band played nationalist songs and a few hundred students waved small Philippine flags. Loud 21-cannon fire thundered in the background. “It will further intensify our patrolling of the Philippines' exclusive economic zone and our capability to quell any threat and bad elements, respond to search and rescue operations and take care of our marine resources,” Aquino told a crowd that included US Ambassador Harry Thomas. In 2011, another US Coast Guard cutter became the Philippine military's largest and most modern warship, the 3,390-ton Philippine navy frigate BRP Gregorio del Pilar. It has patrolled disputed waters and got entangled last year in a standoff with Chinese vessels at the Scarborough Shoal, a sprawling fishing ground more than 260 kilometers (160 miles) west of Subic that came under Beijing's control after Philippine vessels withdrew. The second ship, which was obtained under a US-Philippine military assistance program, signals the Philippines' resolve to upgrade its antiquated equipment and move away from a reputation of being Asia's weakest military. It is not a match for a militarily superior China, but both Philippine and US officials have agreed to bolster the country's defenses to make them more credible. Washington is a defense treaty ally of the Philippines and is obligated to help fend off outside aggression. Also Tuesday, Japan unveiled its largest warship at a naval base in Yokohama. Japan has been locked in a separate and potentially volatile territorial dispute with China over small islands controlled by Tokyo in the East China Sea. The developments point at an arms race by China's neighbors that have been alarmed by Beijing's assertiveness in claiming vast waters and backing those claims by deploying new maritime forces and refurbished vessels. Its claims in the South China Sea overlap with the 220-mile exclusive economic zones of the Philippines and Vietnam. The Philippines antagonized China when it filed an arbitration case with a UN tribunal handling maritime disputes. China has preferred to settle the disputes bilaterally, but the Philippines and Vietnam, which is also engulfed in a rift with China over the Paracel Islands, want to involve the 10-member Association of Southeast Asian Nations. Last week, China's president adopted a more reconciliatory tone, saying that Beijing will continue to guard its sovereignty claims but also wants to open some disputed areas to joint economic development. The Philippines says it is open to the idea but it must conform with Philippine laws — a potential deal-breaker. — AP