The Tokyo Olympics Organising Committee looks set to postpone a decision on domestic spectators until June.
The news comes as the Japanese government looks set to declare a state of emergency in Tokyo due to a fourth wave of COVID-19 infections.
Olympic organisers were set to stage a test athletics event with 20,000 spectators next month, to trial anti-COVID protocols, but that will now go ahead without crowds.
In March, Tokyo Olympics and Paralympics announced that overseas fans would be barred from the Games