By Nick Hope, Apr. 2: The Diving World Cup in Tokyo has been cancelled by the sport's international governing body because the organisers' planned Covid-19 precautions "will not properly ensure" athletes' safety.
In a letter seen by the BBC, Fina also criticises the Japanese government which, in its opinion, "did not take all the necessary measures to ensure successful and fair" competition.
The event was scheduled to run from 18-23 April, and was due to be the final Olympic qualifier and an official test event for the postponed Tokyo Games.
"Fina sincerely regrets this situation," read the letter. "Despite all best efforts and understanding from Fina, the Executive was obliged to take this drastic decision."
Fina informed national federations by email on Thursday after receiving what it describes as "worrying" information about the organiser's proposed Covid-19 strategy, through its task force.
"In their view, this plan will not properly ensure health and protection guarantees to participants," continued the letter.
Some nations had already communicated to the international governing body their intention to withdraw from the event and Fina now aims to find another venue for the competition at a later date.
"We have received an email from Fina last night," said Tokyo 2020 president Seiko Hashimoto. "What kind of measures would make this test event possible and the allocation of dates?"
"I believe there are still many variants which need to be discussed and we haven't been filled in with all the details yet so we would like to continue listening to them [Fina]."
Great Britain had named a full-strength team for the World Cup, including Olympic champion Jack Laugher and three-time world gold medallist Tom Daley.
GB divers were looking to complete their set of Olympic qualification places by securing the remaining berths for the women's individual and synchronised 3m as well as 10m events, with all others having been confirmed through the 2019 World Championships.
It is understood Fina is also unhappy that:
Several Japanese embassies around the world are yet to issue visas to nations who planned to compete
Rising costs associated with Covid-19 countermeasures, which Fina has been asked to pay for
The insistence on a new three-day quarantine prior to the event which would require late changes to pre-booked travel