Multiple Japanese media outlets, citing anonymous sources, said the 83-year-old has told officials he wishes to step down and will announce his resignation at a meeting of Games organizers on Friday.
His most likely successor is Saburo Kawabuchi, an 84-year-old long-time sports administrator, local media reported.
Gaffe-prone Mori, a former prime minister, has come under increasing pressure since remarks he made last week to members of the Japanese Olympic Committee.
"When you increase the number of female executive members, if their speaking time isn't restricted to a certain extent, they have difficulty finishing, which is annoying," he said.
He has apologized for the sexist remarks -- but insisted he was repeating complaints made by others, and dug a deeper hole when he explained that he "doesn't speak to women much".
Public broadcaster NHK and other media said Mori met Kawabuchi Thursday to ask him to take on the role of president.
Kawabuchi, who currently serves in the symbolic role of Olympic Village mayor, reportedly accepted Mori's request.
"If I am elected as president, I would make my utmost efforts," NHK quoting him as saying after the talks.
A former footballer, Kawabuchi played a large part in popularizing the game in Japan in the 1990s.
He played for Japan when the country last hosted the Olympics, in 1964, scoring a goal against Argentina.
- 'Completely inappropriate' -
Mori's resignation would cap more than a week of controversy about his remarks.
Tokyo 2020, which did not immediately respond to a request for comment on the resignation reports, will hold a special meeting tomorrow of its council and executive board.
The meeting was called to allow officials to "express their opinions" on Mori's remarks and discuss "future gender equality initiatives of the Tokyo 2020 organizing committee", organizers said.
Having initially said it considered the matter closed with Mori's apology, the International Olympic Committee branded his remarks "completely inappropriate" as the backlash grew.
An online campaign calling for action against Mori has attracted more than 146,000 signatures, while tennis superstar Naomi Osaka slammed his comments as "ignorant".
Since Mori's remarks, around 400 Olympic and Paralympic volunteers have quit, according to Tokyo 2020, which has said the number includes withdrawals for all reasons.
A total of 80,000 volunteers from Japan and overseas have been recruited for this summer's virus-postponed Games.
Games sponsor Toyota on Wednesday issued a statement by its president Akio Toyoda saying: "It's very regrettable that the comments made by the leader of the organizing committee differ from the values that Toyota holds."
Tokyo's governor turned up the heat further on Wednesday, saying "I won't be attending" four-party Olympic talks expected to involve IOC head Thomas Bach later this month.
"I don't think a four-party meeting would deliver anything positive," Yuriko Koike said, without further explanation.
Organizers are already facing public opposition to holding the Games this summer, with polls showing around 80 percent back either further postponement or a cancellation.
Parts of Japan, including the capital, are currently under a virus state of emergency, and the first vaccine approval in the country is only expected next week.
In a bid to bolster support, organizers and Olympic officials have released a series of virus "playbooks" with rules they say will ensure the Games can be held safely even if the pandemic is not under control by the opening ceremony, scheduled for July 23.
© 2021 AFP
