MANILA - The Philippines may ask the United States to deploy spy planes over the South China Sea to help monitor the waters, President Benigno Aquino said on Monday.

The United States has stressed it is neutral in the long-running maritime dispute, despite offering to help boost the Philippines' decrepit military forces.

"We might be requesting overflights on that," Aquino told Reuters in an interview, referring to US P3C Orion planes. "We don't have aircraft with those capabilities."

In Washington, State Department spokeswoman Victoria Nuland declined to comment on the Orion aircraft, but said Washington has long assisted Manila, a formal security treaty ally.

"As part of our longstanding military cooperation, the United States supports the Philippines in enhancing its maritime domain awareness," she told a news briefing.

"We are talking about helping the Philippines be aware of what is going on and supporting our ally in defense of its own security," added Nuland.