TOKYO - Philippine President Rodrigo Duterte will not call on Emperor Akihito on Thursday (Oct 27) as was initially planned, The Straits Times has learnt.

The call was cancelled following the death of Emperor Akihito's uncle, Prince Mikasa, on Thursday morning. He was 100.

On Thursday afternoon, Mr Duterte told reporters after a visit to the Yokohama Maritime Disaster Prevention Base of the Japan Coast Guard: "I'd like to express my deepest condolences (to the Emperor). I hope the protocol officer would allow me not to go there because they are in mourning."

The Philippine leader is on a three-day introductory visit to Japan which he has described as a "special friend who is closer than a brother".

Both countries mark 60 years of bilateral ties this year.

Mr Duterte, who is known for his crude language, had worried Japanese officials that he might chew gum in front of the Emperor, as he had done during his meeting with Chinese President Xi Jinping last week.

Mr Duterte will return to the Philippines on Thursday evening .