MANILA - Associate Justice Antonio Carpio on Thursday said the Philippine government should ask the United States to recognize Scarborough Shoal as part of Philippine territory.

• 5 facts on Scarborough Shoal

Carpio said that when the Americans colonized the Philippines, the US already recognized that the shoal is part of Philippine territory. He said official communications from the US to Manila show Scarborough Shoal is part of Philippine territory and is thus covered by the Mutual Defense Treaty.

However, when the Chinese "seized" the shoal in 2012, the Obama administration refused to take sides in the territorial disputes in South China Sea.

"[The US should] recognize [that] because right now, it looks like they do not recognize it because they said we cannot intervene in Scarborough Shoal because we don’t take part in territorial disputes," he said in an interview with ANC's Headstart.

"Scarborough Shoal is not something disputed because they already recognized that," he added.

Carpio said the Philippine government should ask a "clarification" from the US, its longtime ally, on whether or not the shoal is covered by their defense agreements.

"We want a clarification from the US. All your records show that Scarborough Shoal is part of Philippine territory. Now, we want a statement from you—is that rock covered by that treaty, mutual defense treaty," he said.

Failure to do so, added Carpio, will put the US in a bad light in relation to its other mutual defense treaties with other nations, such as Japan and South Korea.

"If US is seen to be reneging—when there is an encroachment, they will say that is not part of your territory when during the time the treaty was signed that was part of the territory—then US credibility will fall, nobody will believe them anymore," he said.