The International Olympics Committee has reminded athletes not to hug on the podium and keep their masks on as they celebrate their achievements at the Tokyo Games.
The reminder from the IOC comes after athletes were seen congratulating each other on the podium after the swimming competition on Sunday. Some athletes also removed their masks on the podium. This breaches the Olympics "playbook," a set of guidelines for the Summer Games.
"We would urge and ask everyone to obey the rules, whatever stakeholder you are," IOC spokesperson Mark Adams said Sunday. "It is not a nice to have, it is a must have, both for the sports and for everyone involved.
"It sends a strong message so please follow the playbooks. We understand there is excitement and we feel for the athletes, but unfortunately we have had to make the rules stricter.
"These messages are constantly passed, not just to athletes. It is in our interests and the interests of everyone."
American Chase Kalisz took off his mask on the winners' podium after his gold medal performance in the men's 400 meters medley, hugging compatriot and silver medalist Jay Litherland, who was without a mask. Australian Brendon Smith, who took the bronze, also removed his mask.
"Ideally I will wear it as much as possible. If I had the mask off on the podium it was really because someone was holding a sign," Kalisz said. "I can't speak for what the proper protocol was, but he had a sign on the podium that said mask off, mask on, so that's what we did."
A little later, all 12 athletes from Australia, Canada and the United States on the podium for the women's 4X100 freestyle relay ceremony were without masks, hugging teammates and smiling to photographers.
On Saturday, medal winners in judoka were also seen taking group photos on the top step of the podium.
Information from Reuters was used in this report.