The competition at Yoyogi National Gymnasium will see major international sport return to the Olympic host city for the first time since the coronavirus outbreak.

With officials currently debating how to hold next year's postponed Tokyo 2020 Games safely, the gymnastics action will provide a valuable learning experience. 

"The world will be watching us," said Watanabe.

"While sports also need to live with the unknown virus, we will ensure solutions to the issues one by one, and will strive for creating the environment where mental support is provided to gymnasts."

China, Russia and the United States are due to join Japan at the event.

A number of virus restrictions will be place, including daily COVID-19 testing.

"There have been people saying it's medically meaningless (to conduct daily testing) but we can't host the event thinking some athletes might be infected with the coronavirus," Watanabe added to Kyodo News.

Two teams will contest the event – team friendship and team solidarity – with eight male and eight female gymnasts on each.

Every gymnast from visiting teams has been required to quarantine for two weeks before leaving, while movement in Tokyo will be restricted to the venue and official hotel.

Teams have arrived in Japan on charter planes and athletes were kept away from other passengers after landing at the airport.

Each team has its own reserved floor at the hotel, which is monitored by security guards.

Fans will be allowed to attend the event, but capacity will be restricted to 2,000.

The competition has already survived a scare after Japanese star Kōhei Uchimura tested positive for coronavirus last week.

The 31-year-old three-time Olympic gold medallist has since provided three negative tests, however, and the rest of the Japanese squad have also been given the all clear.

If the virus had spread through the home delegation the event would have been cancelled.