Tokyo Olympics organizers have warned that they are prepared to hold the Games behind closed doors as virus cases rise, leaving ticketholders in limbo just barely three weeks before the opening ceremony.

Seiko Hashimoto, president of the Tokyo 2020 organizing committee, said on Friday that banning all fans from the Olympics is still an option with the Games opening during a pandemic.

The latest announcement would be a reversal of a decision spelled out 10 days ago by the organizers to allow up to 10,000 fans to attend.

Overseas traveling fans were banned months ago as too great a risk.

The possible about-face is being forced by rising new infections in Tokyo, the appearance of the rapidly spreading Delta variant, and fears that the Olympics and Paralympics with 15,400 athletes and tens of thousands of others entering Japan could turn into a super-spreader event.

“The situation of infection changes and how it will be is still unclear,” Hashimoto said in a Friday briefing. “But from Tokyo 2020’s perspective, we also include an option of not having spectators.”

Yet another decision on fans could be announced this week after a meeting of the International Olympic Committee, local organizers, the Japanese government, Tokyo metropolitan government officials, and the International Paralympic Committee.

The government’s top COVID-19 adviser, Dr. Shigeru Omi, has said repeatedly that the safest option is without any fans.

And Yuriko Koike, the governor of Tokyo, suggested on Friday that has been her preference, too. “We will continue to closely watch the infection situation and think what would be best, and mainly consider no spectators,” Koike said.