Swimming's world governing body FINA is considering cancelling three qualifying events in Japan ahead of this summer's Tokyo Olympics due to coronavirus and cost concerns, a source close to the matter said Friday.

According to the source, FINA and the games organizers are mulling whether to cancel the April 18-23 diving World Cup at the Tokyo Aquatics Center, the May 1-4 artistic swimming qualifier in Tokyo and the May 29-30 marathon swim qualifier in Fukuoka.

The reason given for the possible cancellations has been FINA's inability to agree with Japanese organizers on the burden of coronavirus countermeasure costs.

The move follows a spate of cancellations among the 600 athletes and officials originally planning to travel from over 40 countries and regions to the diving meet, which was to serve as an Olympic test event.

FINA had already rescheduled the artistic swimming qualifier, the first Olympic test event with COVID-19 countermeasures in place from March 4-7. The international federation is expected to bear the financial burden of the strict quarantine measures needed and is therefore reluctant to hold these events.

The Tokyo Olympics and Paralympics Organizing Committee President Seiko Hashimoto said the organizers have received a letter from FINA, adding that there has been "no detailed explanations yet" and "postponement of the event or staging it at an alternative site is unrealistic."

The risk of coronavirus infection among athletes and officials as well as the fairness of the competition are thought to be some of the factors behind FINA's stance. Allocations of Olympic slots to countries and regions that would have been settled at the Tokyo competition will need to be sorted out if the event is canceled.

The FINA Diving World Cup was expected to feature the best divers from around the world in the 3-meter springboard and 10-meter platform in both individual and synchronized events.

The event was postponed from April last year due to the pandemic.