Representatives from the two European cities confirmed to insidethegames that presentations would be made to FINA tomorrow afternoon, with an announcement of the host cities expected at around 7pm local time.

Kazan in Russia and Hungarian capital Budapest were awarded the 2022 and 2024 FINA Short Course World Swimming Championships in 2017 and another double allocation is likely, but it is understood that at least two other unconfirmed cities could be making presentations tomorrow.

In November 2018, seven countries declared an interest in hosting the 2025 and 2027 World Aquatics Championships, with Melbourne in Australia, Belgrade in Serbia, Greensboro in the United States among the contenders.

China and Ukraine also entered the running without confirming their candidate cities.

In May, Greensboro pulled out of the race stating a "walk-before-you-can-run" approach to international championships was needed before jumping into the staging of World Championships.

The World Aquatics Championships are held every two years and feature more than 2,300 of the world's elite athletes in artistic swimming, diving, high diving, open water swimming, swimming and water polo.

The next FINA World and Masters Championships are due to be held in Fukuoka in Japan in 2021 and Doha in Qatar in 2023.

The World Championships and FINA World Masters Championships, an event for competitors aged 25 and over, have been held jointly since 2015 when they were staged in Kazan.

If Kazan's bid for either 2025 or 2027 is successful, they would join a select group of cities who have hosted the FINA World Championships more than once. 

The only other cities to have staged two are Rome in 1994 and 2009, Perth in Australia in 1991 and 1998 and Barcelona, in 2003 and 2013.