Duterte attended Japanese Emperor Naruhito's enthronement ceremony in Tokyo on Tuesday, at times using a cane and appearing to stand stiffly. In other photos sent by an aide to the media in Manila, the 74-year-old president appears to be in a light mood as he, his daughter and an aide extend their fists forward in a symbolic gesture associated with Duterte.

Presidential spokesman Salvador Panelo said Duterte would fly back to the Philippines later Tuesday and see his neurologist Wednesday but assured the public that the president's health was not worrisome.

"The palace announces that the president will cut short his trip to Japan due to unbearable pain in his spinal column near the pelvic bone as a consequence of his fall during his motorcycle ride," Panelo said in a statement. "While this was unforeseeable, the public can rest assured that there is nothing to worry as regards the physical health and condition of the president."

As a result, Durterte was to miss a banquet for the Japanese emperor that was to instead be attended by his daughter, Sara Duterte, who is mayor of Davao city, the Dutertes' hometown and political bailiwick in the southern Philippines.

An avid rider of big motorcycles in his younger days, Duterte sustained bruises and scratches when he fell off his parked motorcycle last Thursday in the sprawling presidential palace complex in Manila, but Panelo said then that the president's minor injuries would not affect his schedule.

Duterte said last year that he suffers from "perpetual pain" due to a spinal injury he sustained in a motorcycle accident many years ago. He has also acknowledged using Fentanyl, an opioid used to treat chronic pain that can also be used as a recreational drug.

A lack of regular medical bulletins on the president's health has sparked sporadic speculation about the state of his health, especially when he failed to appear in public for days in recent times.

When Duterte did not show up in public for more than a week in August, Panelo explained that the president was busy reviewing documents he needed to sign but stressed he was healthy because he even managed to bike around in Davao.

"He got enthusiastic and rode out of the village enclave on a motorcycle, alarming the Presidential Security Group," Panelo told reporters then.