People walk by signage to promote the Olympic Games in Tokyo, Monday, April 5, 2021. (Photo: AP)

This summer's virus-postponed Olympics could be held behind closed doors, Tokyo 2020 president Seiko Hashimoto told AFP on Friday, pledging to ensure the Games will be safe.

"There might be a situation where we can't allow any spectators to attend," she said in an interview, adding the Games would only be a success if organisers "completely protect" athletes and the Japanese people.