TOKYO - President Rodrigo Duterte will not be visiting Emperor Aikihito of Japan, following the death of the Japanese monarch's uncle Prince Mikasa.

Duterte said he was told by a protocol officer not to visit the Emperor because the royal family was in mourning over the passing of the 100-year-old prince.

"I respect that. I would ask for the same request if I were in his shoes," he said during an ambush interview on Thursday.

"I'd like to express my deepest condolence," he added.

Prince Mikasa, the youngest brother of the current emperor's father, died Thursday, according to the Imperial Household Agency.

Duterte is in Japan for a three-day official visit. He has already met with Prime Minister Shinzo Abe and the Filipino community in Tokyo.

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Some Japanese have expressed concern that Duterte may not follow protocol in meeting the emperor, the most revered figure in Japan.

This, after a video of him in China last week meeting with President Xi Jinping showed him apparently chewing gum -- considered rude in Japan for such an occasion. He was also seen standing at the event with his hands in his pockets, another no-no.

Since arriving in Tokyo on Tuesday, Duterte has avoided any major trouble, though he has kept up a barrage of insults against Washington. -- With a report from Agence France-Presse