Olympic medallists are now allowed to remove their masks on the podium, for a 30-second, socially distanced photo-op.That's the new rule from the International Olympic Committee, but it confirmed on Sunday that masks are otherwise mandatory across all Tokyo Games venues, at all times, including medal ceremonies, for staff, athletes and media.Spectators have mostly been absent from the Games.This was IOC spokesman, Mark Adams:"There is no relaxation and we would urge and ask everyone to obey the rules, whatever stakeholder you are, us, the IOC, media, athletes, everyone. It's not a nice to have, it's a must have. It's important both for the sports and for everyone involved and of course for our Japanese partners and friends particularly also. It also sends a strong message."During Sunday morning's swimming finals, American Chase Kalisz took off his mask on the winners' podium after his gold medal performance in the men's 400 meters medley.He was standing next to mask-less compatriot and silver medallist Jay Litherland and Australian Brendon Smith, who took the bronze and also removed his mask.The IOC confirmed the swimmers were abiding by the changed rules.