The head of the Tokyo 2020 organizing committee has not ruled out a cancellation of the Olympic Games, the BBC reports.
Toshiro Muto said he would keep an eye on infection numbers and hold “discussions” if necessary.
More than 70 people associated with the Games have tested positive ahead of Friday’s opening ceremony.
His comments came on the same day International Olympic Committee (IOC) president Thomas Bach said cancellation was “never an option”.
Earlier this month, Japan announced the Games would go ahead in empty venues without spectators – despite growing concern over the Covid situation.
“We will continue discussions if there is a spike in cases,” said Mr Muto when asked at a press conference if the Games might be cancelled even at this late stage.
“At this point, the coronavirus cases may rise or fall, so we will think about what we should do when the situation arises.”
The opening ceremony of the Olympic Games is due to kick off on 23 July, though the first event of the Games – a softball game between Japan and Australia, took place on Wednesday.
The Olympics will end on 8 August, with the Paralympic Games due to start on 24 August and to end on 5 September.