Qualifying trials for three of the United States' Olympic sports, athletics, swimming and gymnastics, have been postponed for 2020 officials said on Tuesday after the Tokyo Games were delayed a year because of the coronavirus pandemic.

All three sports have top teams and major prospects for the Olympics which will now be held in 2021 - four-times gold medallist Simone Biles in gymnastics, swimmer Katie Ledecky, winner of five Olympic gold medals, and world sprint champions Christian Coleman and Noah Lyles in athletics.

"Tracktown US is now working with our partners at US Track & Field (USTF) and the US Olympic and Paralympic Committee (USOPC) in rescheduling the US Olympic Team Trials - Track and Field," organisers for the previously scheduled June 19-28 competition in Eugene, Oregon, said in a statement.

US Swimming and US Gymnastics made public similar postponements in statements to Reuters.

The US Olympic swimming trials had been scheduled for June 21-28 in Omaha, Nebraska with the gymnastics trials for June 25-28 in St. Louis, Missouri.

Olympic sources told Reuters new dates for all US trials could not be set until the International Olympic Committee (IOC) determines the 2021 dates for the rescheduled Tokyo Games.

Other factors including timing and the availability of venues and broadcast networks must also be considered, the sources said.

The delayed Olympics are likely to mean the 2021 world athletics championships, scheduled for Eugene, would be pushed back to 2022, World Athletics president Sebastian Coe has suggested.

That would prevent the challenge of having both the US Olympic trials and the world championships being held within months of each other in Eugene, a city of about 170,000 where a new athletics stadium is being built.

"US Gymnastics will work together with the USOPC (United States Olympic Commnittee) and the St. Louis Sports Commission to reschedule the Olympic Trials, once the new dates for the Olympics Games have been set," the federation said.

"We are hopeful that we will be able to hold Olympic Trials in St. Louis in 2021."

US Swimming president Tim Hinchey said his organisation would seek to schedule a calendar of events that properly preapres the team for 2021.

"We will work closely with the USOPC on rescheduling the US Olympic Team Trials-Swimming to best align with Olympic Games preparations as further details become known," he said in a statement. 

Reuters