Yoshiro Mori, who recently revealed he has had surgery to treat lung cancer, said Monday he is considering resigning as president of the Japan Rugby Football Union but still intends to retain his post as chief of the 2020 Tokyo Olympics organizing committee.

"I've been thinking for a while that I will have to quit sometime. I want to slow down the pace," said the 77-year-old Mori, who has served five terms as head of the JRFU since 2005.

Mori, who took the helm of the organizing committee in January 2014, had an operation to remove cancer in his left lung on March 23.

The former prime minister, who has spawned criticism over the years for many gaffes despite his strong political and business connections, admitted to burning the candle at both ends.

"In reality it isn't good that I assume responsibility for both the Olympics and the (2019) Rugby World Cup (in Japan)," said Mori. "Also, I shouldn't be pushing myself too much physically."

Mori, who has not mentioned a successor, said he had conveyed his intention of resigning to the JRFU at the end of last year.

Tadashi Okamura, 76, a former president of the Japan Chamber of Commerce and Industry and finance chairman of the 2019 Rugby World Cup organization's committee, is a candidate to succeed Mori.

"(The new president) will be a person who from the standpoint of organizing a World Cup is well versed in a wide area, including politics, business, bureaucracy and sports," said Mori.