President Rodrigo Duterte did not commit "estafa" by supposedly fooling the Filipinos when he made promises about the West Philippine Sea when he was still campaigning for president, Malacanang said on Wednesday.

"As a former justice, he knew the elements of estafa and he knew that this is not estafa," Presidential Spokesperson Harry Roque said, referring to retired Supreme Court Associate Justice Antonio Carpio.

"It's not fooling (the people) because the President's words are clear. He did not say that the lost territory during the past administration will be retaken. What he promised was, there will be no territory that will be lost from the Philippines, which is happening now," he told reporters in an interview in Quezon City.

Carpio has accused Duterte of committing grand estafa or grand larceny by making false promises to get 16 million votes during the presidential campaign.

He has said Duterte could not deny that he never discussed or mentioned the West Philippine Sea issue when he was campaigning for president. Otherwise, he said the former Davao City mayor would be admitting that he was fooling the Filipino people big time.

In his "Talk to the People" last Monday, Duterte said he never promised the people that he would retake the West Philippine Sea nor promised to pressure China.

He has also denied mentioning about the territorial dispute between the two countries as the issue has to be resolved diplomatically through the Department of Foreign Affairs.

Roque lamented that the territorial dispute is a serious issue and yet Carpio has resorted to "name calling."

"He is now talking as a politician...if the President is a swindler, how are we going to call him because he himself penned the decision wherein we lost huge part of our territorial sea and internal waters. But we will not stoop down to his level," he said.

The Supreme Court's decision that Carpio penned and which Roque was referring to was the Magallona vs. Ermita case in 2011. The high tribunal upheld the constitutionality of Republic Act No. 95221, adjusting the country’s archipelagic baselines and classifying the baseline regime of nearby territories. Celerina Monte/DMS