Manila: Philippine President Rodrigo Duterte says he used to be gay but "cured" himself by marrying beautiful women, drawing outrage from at least one human rights group.

Duterte, in Japan last week, was speaking to members of Tokyo's Filipino community when he appeared to mock political opponent Senator Antonio Trillanes. Duterte said a gay person told him Trillanes appeared to be gay, the Philippines website Rappler reported.

Philippine President Rodrigo Duterte delivers a speech in Tokyo. Credit:AP

"I said, 'Are you sure?' They said, 'You ask any gay person who sees [him] move, they'll say he's gay,' " Duterte said. "No wonder. Good thing Trillanes and I are similar. But I cured myself."

Duterte said his ex-wife, Elizabeth Zimmerman, was the reason why, according to Rappler. Zimmerman was a flight attendant when they married in 1973. They split in 2000.