Olympic chief Thomas Bach says "all options are on the table" over finding a new date to hold the postponed Tokyo Games.
Tokyo 2020 became the first Olympics in peacetime to be postponed due to the coronavirus pandemic.
Announcing the unprecedented decision on Tuesday, the International Olympic Committee (IOC) gave no specific new date, saying only it would be "beyond 2020 but not later than summer 2021".
On Wednesday in a conference call, IOC president Bach said: "This is not restricted just to the summer months.
"All the options are on the table, before and including the summer of 2021."
World Athletics said on Monday it was prepared to shift its world championships in 2021 in order to accommodate a rescheduled Games.
The world championships are due to be held in Eugene, Oregon on 6-15 August next year.
And the International Swimming Federation (FINA) said on Tuesday that it was open to moving next year's world championships to fit in with the rescheduled quadrennial sporting extravaganza.
The swimming worlds are set to be held in Fukuoka in Japan between 16 July and 1 August next year.