The president of the Philippines made a direct pitch to the White House Friday to help bolster his country’s relatively weak defenses as the island nation increasingly finds itself tangled in territorial conflicts with China.

The Philippines, a former colony and longtime ally of the United States, has been seeking reassurances that Washington would come to its defense in a confrontation with China. The two Asian countries assert overlapping claims in the mineral-rich South China Sea and have been engaged in a two-month standoff over a rocky outcropping there.

China claims sovereignty over much of the South China Sea, alarming countries such as the Philippines, Vietnam and Malaysia, whose coastlines are much closer to some of the disputed territories.

That has led to a rapid souring of relations between Beijing and Manila, with Philippine leaders expressing concern about China’s strategic ambitions in the region.

“If you’re asking me to discern their intentions, frankly we’re still analyzing what their intentions are,” Philippine President Benigno Aquino III said in an interview with editors and reporters of The Washington Post on Friday prior to his visit to the White House, where he met with President Obama.

China has the most powerful military in Asia and is boosting its spending on defense. The Philippines, in contrast, lacks a single fighter jet. Its navy is so weak that its biggest warship is an aging former U.S. Coast Guard cutter it acquired as surplus from the Pentagon last year.

Aquino’s government has intensified talks this year with the Obama administration about expanding the U.S. military presence in the Philippines. Among the options under consideration are operating Navy ships from the Philippines, deploying troops on a rotational basis and staging more frequent joint exercises.

The welcome mat from Manila represents a turnaround. In 1992, the Philippines evicted the U.S. military from its sprawling naval base at Subic Bay, a year after the Pentagon had abandoned nearby Clark Air Base. Together, the two bases had served as a cornerstone of the U.S. military presence in Asia for nearly a century.

In the interview with The Post, Aquino said his government wanted the Pentagon’s help to upgrade its maritime surveillance capabilities so the Philippines — which has 7,107 islands — can better patrol its extensive coastlines.

He said the U.S. deployment of surveillance aircraft, such as Navy P-3C Orion planes and Global Hawk drones, would be “a welcome development.” But he said the Philippines was particularly interested in acquiring a land-based radar that could enable it to monitor the wide expanses of the South China Sea.

Felix K. Chang, a senior fellow at the Foreign Policy Research Institute in Philadelphia, called a radar “a significant step in improving the Philippines’ situational awareness off its coasts.” He said Manila’s defenses are so poor that often it has “only learned about foreign activities after the fact.”

Rick Fisher, an Asian security expert at the International Assessment and Strategy Center in Alexandria, said a powerful land-based radar could be used jointly by the Philippines, the United States and other allies to quickly detect Chinese military movements in the region. That would fill a void that has existed since the U.S. military was evicted from Subic Bay and Clark two decades ago.

Such a radar could provide “an almost instant way of keeping the Chinese honest,” Fisher said.