MANILA - President Rodrigo Duterte on Tuesday insisted that the Philippines cannot wage war against China over Beijing's sweeping claims in South China Sea.

"That’s why sabi ko, 'hayaan mo lang ang China.' Hindi naman natin ma-giyera, we cannot retake it. I went to China to buy arms. Anong sabi ni Xi Jinping? ‘Yung kumprotasyon namin diyan sa China," Duterte said in a speech at the 117th anniversary of the Office of the Solicitor General in Pasay.

"Naglalaro ako ng baraha dito, wala man rin akong magawa, dito muna ‘yang China. ‘Pag year 4001, tigas na tayo, invade natin ‘yung China, kunin natin ‘yung oil natin. By that time, i-straw mo, wala na. Maski bunbon (Bisaya for sand)."

China has built artificial islands in the South China Sea and equipped them with runways, missile systems, and communication facilities.

It also recently deployed military aircraft to a base it built on a reclaimed island in the disputed sea, indicating Beijing is now moving to further cement its military presence.

Duterte earlier said it is pointless to question China’s deployment of its air assets to its artificial islands in the Spratlys.

He has also claimed Chinese President Xi Jinping threatened war if the Philippines drilled for oil in the disputed waters.

The Philippines and China have for decades been embroiled in a dispute over the South China Sea. It reached a critical point during the presidency of Duterte’s predecessor, Benigno Aquino III, who approved the filing of a case against Beijing before the Permanent Court of Arbitration in 2013.

The tribunal ruled in favor of Manila in 2016, declaring China’s expansive nine-dash line claim to the sea invalid. Beijing has ignored the landmark ruling.

Duterte said he won’t raise Manila’s victory yet, noting the Philippines is benefiting from the friendly ties between the two Asian nations.