While the President has attracted criticism overseas—human rights activists have accused him of state abuse over the extrajudicial killings from his narcotics crackdown—he remains immensely popular among Filipinos, who praise him for tackling a key source of crime and violence. Nearly 6,000 have died since the war on drugs began in July, out of which 3,841 were vigilante-style killings, according to new Philippine police data on Monday.
On Monday, Duterte shocked the world yet again after hinting that he personally killed criminal suspects during his reign as Davao City mayor, corroborating similar statements made throughout his presidential campaign. In December last year, he told a local radio station that he shot three kidnappers in 1998.
People should not overreact to his comments, insisted the man tasked with the tough job of heading Duterte's public relations team.
"The President talks like that, we should not take his comments literally because he wants to instill fear in the minds of criminals," Martin Andanar, secretary of The Philippines' presidential communications office, told CNBC's "Street Signs" on Thursday. When listening to the President's remarks, the public needs to read between the lines, he continued. "In one to ten of the President's speeches, there are maybe five that you need to decipher."
With no concrete deals expected on this Singapore trip, foreign policy could feature prominently on the agenda.
"Singapore will likely be very interested in Duterte's policy, particularly towards the U.S. and China," said Cook, referring to the Philippine leader's efforts to distance himself from Washington and cozy up to Beijing.
The Philippines will also be chairing the Association of Southeast Asian Nations (ASEAN) bloc next year, followed by Singapore in 2018, so discussions on regional diplomacy are also likely.
"Presumably, there are concerns in the region of a more inward-looking U.S. foreign policy in the coming years under President-elect Trump, so leaders may prioritize strengthening defense ties," explained Kevin McGahan, political science lecturer at National University of Singapore.
In Phenom Penh on Tuesday, Duterte announced that old age and health issues, which range from migraines to Buerger's disease, might prevent him from finishing his six-year term. But Andanar dismissed those fears on Wednesday, noting that the President was "in tip-top condition and in the pink of health."
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