Emperor Akihito and Empress Michiko will not attend the official annual memorial service for the 2011 tsunami-quake disaster on March 11, Chief Cabinet Secretary Yoshihide Suga said Friday.

Instead, Prince Akishino, their second son, and his wife, Princess Kiko, will attend the ceremony. Suga said the decision is not related to the ongoing government inquiries into whether an emperor should be allowed to abdicate, though he did not elaborate.

"It has nothing to do with the issue (of easing the Emperor's burden of public duties). In a sense, it is only natural" that Akishino will attend on behalf of the Emperor, Suga said.