Japan's emperor says may be 'difficult' to fulfil duties

Japanese Emperor Akihito said on Monday he is concerned his weakening health may make it hard to fulfil his duties, in a speech seen as flagging a possible future abdication.

"I am worried that it may become difficult for me to carry out my duties as the symbol of the state with my whole being as I have done until now," he said in an address to the nation.

"There are times when I feel various constraints such as in my physical fitness," the 82-year-old said.

Akihito spoke obliquely, but the government is expected to interpret his comments as meaning his wish is to eventually step down. It can then begin creating the necessary legal mechanism which currently does not exist.

Prime Minister Shinzo Abe in a swift response to the emperor's speech said the government would take the emperor's remarks "seriously".

"Considering the emperor's duties, as well as his age and the burden (of the job), we have to firmly look at what we can do."

Speculation about the emperor's future emerged last month with reports he had told confidantes that advancing age was making it harder to perform his ceremonial duties and that he would like to step down in a few years.

The address marked only the second time for Akihito to speak directly to the nation, the first having been in the days after the March 2011 triple earthquake, tsunami and nuclear disaster as he sought to calm a nation undergoing its worst crisis since the war.