TOKYO - Japan's Emperor Akihito marked his 83rd birthday Friday, thanking the people for their concern and effort to accommodate his apparent abdication wish.

"I am profoundly grateful that many people have lent an ear to my words and are giving sincere thought to the matter in their respective positions," Akihito said in birthday remarks, released Friday.

Akihito also greeted thousands of well-wishers from the palace balcony, along with other members of the royal family, including his son, Crown Prince Naruhito, his heir apparent.

Akihito, in a rare address in August, indicated his wish to abdicate, citing concerns that his age and health conditions may start limiting his ability to fulfil his duties.

That message was to express "what has been on my mind over the last few years, reflecting on my years as the emperor and contemplating on my role and my duties as the emperor in the days to come," he said.

A government-commissioned panel of experts is discussing a possibility of enacting a special law allowing his abdication, without touching more controversial issues, such as an option of allowing a female emperor, and how to address concerns of a shortage of successors to the Chrysanthemum throne.

The abdication issue renewed concerns about aging and shortage of successors in the Imperial family - a 2000-year-old monarchy - which reflects overall concerns about Japan's declining population and rapidly aging society.

Akhito and his wife Michiko have two sons - Naruhito and his younger brother Akishino - but after that, only one of the four grandchildren is eligible to the throne under Japan's male-only succession system.

Current law, set in 1947, is largely inherited from a 19th-century constitution that banned abdication as a potential risk to political stability.