The Pentagon sent two US warships through the waters of the South China Sea over the weekend, a public demonstration of the right of free passage in global waters and, in the process, sending China a message.
But if deemed necessary, Esperon said, the Philippines will look into the option of fighting back if China will coerce or hurt Filipino troops and civilians based on the islands located in disputed areas.
Esperon also clarified that Duterte administration still observes the actions of the various claimants in the disputed South China Sea.
Marco Rubio and Cory Gardner, expressed "grave concerns" over Beijing's actions and stated that "we believe there is strong bipartisan congressional support for taking significant actions in response to the Chinese government's continuing militarization of the South China Sea".
China claims almost the entire South China Sea, despite overlapping claims with other countries, including Vietnam, the Philippines, Malaysia, Brunei and Taiwan. "We're very open about them".
"The president has said that".More news: Where's Melania Trump? First lady not seen in public for three weeks
Political analyst and youtuber Black Pigeon Speaks explains why the investment that China is making to militarize the region is only useful for psychological and propagandistic purposes, and would serve nearly no strategic value if directly challenged by the US military.
Cayetano's remarks apparently contradict the president's prior statements that he preferred to maintain friendship with China rather than engage it in a war over the two countries' territorial disputes.
China dispatched heavy bombers to contested territories in the region in mid-May.
Speaking at a separate briefing, defense ministry spokesman Ren Guoqiang said they had noted that the United States had recently been "turning a blind eye to the facts and hyping up" the militarization of the South China Sea.
Five lighthouses on five islands in the Spratlys - Pag-asa Island, Likas (West York) Island, Parola (Northeast Cay) Island, Kota (Loaita) Island and Patag (Flat) Island - will be built, Esperon said.
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But after pounding on the Aquino administration's alleged failures, Cayetano said, "We're not blaming the past administration, some critics are making it appear na iba ang situation ngayon".
He noted that Chinese President Xi Jinping promised at the White House in 2015 that China would not be militarizing areas near the Spratly Islands, but the USA saw last month that it had done exactly that, moving in weaponry that was not there before.
Manila is pursuing a joint exploration agreement with Beijing for oil and natural gas reserves in their claimed territory in the South China Sea.
U.S. Navy Adm. Philip Davidson will take over PACOM from Adm. Harry Harris during the change of command on Wednesday.
National security and defence experts have said that the military operations being conducted by the Pentagon are mainly symbolic and that they have no impact on how China will behave going forward.
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