Concerning his surprise announcement, Duterte, who took office in 2016 for a six-year term of presidency, said that he is heeding the Filipinos' "overwhelming sentiment" for him to quit politics.

"The universal sentiment of the Filipinos is that I am not qualified. It would be a violation of the constitution to circumvent the law, the spirit of the constitution.

"And so in obedience to the will of the people who, after all, placed me in the presidency many years ago, I now say to my countrymen I will heed your wishes," Duterte said.

He was at the poll body on Saturday in Metro Manila to accompany his former long-time aid and Senator Christopher Go, 47, who filed his candidacy for Vice President.