(FILES) In this file photo taken on May 18, 2021, security guards keep watch next to the Olympic Rings while people take part in a protest against the hosting of the 2020 Tokyo Olympic Games, in front of the headquarters building of the Japanese Olympic Committee in Tokyo. - The United States warned its citizens on May 24, 2021 not to travel to Olympic host Japan, citing the growing risk of the Covid-19 pandemic in the Asian nation just two months before the Games begin. (Photo by Kazuhiro NOGI / AFP)