Prime Minister Yoshihide Suga is lamenting drawing so much criticism for Japan's hosting of the Olympics during a pandemic, while his government is reported to favor allowing domestic spectators into stadiums to watch.

Many Japanese people and medical experts oppose staging the 2020 Games as planned from July 23, after already being postponed a year, as their nation suffers a fourth infection wave.

Suga, who is expected to call a snap election after the event, has staked his political reputation on going ahead with the Olympics, which he has said will bring joy to the world and be safely conducted within a "bubble."