A senior official of the International Olympic Committee (IOC), John Coates, said it was "100%" likely that the Games would go ahead in Tokyo this summer, Nikkei Asia reported on Thursday.
Coates also told Nikkei Asia in an interview that the decision on whether spectators will be allowed to attend the July 23 - August 8 Games will be made as soon as March or April.
"It's difficult. It's difficult but the Games will take place," he was quoted as saying.
"The IOC and the Tokyo Organising Committee, the Japan government, the Tokyo municipal government have been determined to host these games since the pandemic broke in February last year. We've maintained our resolve. And we see no impediment to that."
Coates, an Australian, is vice president of the IOC and chairs Tokyo 2020's coordination commission. Support for the Games has evaporated in Japan as the coronavirus crisis has worsened.
Nearly 80% of the Japanese public are now opposed to holding the Summer Games as scheduled this year, recent polls show.
On Thursday, the head of Tokyo 2020 and a former prime minister, Yoshiro Mori, apologised for sexist comments about women talking too much, but said he would not resign.
His remarks sparked a storm of criticism on social media and risked further tainting public opinion of the Games.
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