Rescheduling Tokyo 2020 is like "a huge jigsaw puzzle" and the new date "will not be restricted to the summer months", says the International Olympic Committee's president.
It was announced on Tuesday that the Olympic and Paralympic Games have been delayed until next year because of the worldwide coronavirus pandemic.
Thomas Bach said there are "many thousands of questions" to address before a new timeframe can be confirmed, but added that "all options are on the table".
Explaining the sequence of events that led to the postponement - the first in the 124-year modern history of the Olympics - Bach said the International Olympic Committee (IOC) received an "alarming" update from the World Health Organization but the final decision could not be "unilateral".
"In order to organiser a successful Games we need to be in full agreement and we need to be united," the German added. "For a postponement we need, of course, the full commitment of our Japanese partners.
"That was what we were looking for with our approach and what we achieved."
Speaking on a conference call, Bach said a special taskforce, named "Here We Go", has been set up to tackle the logistics of reorganising Tokyo 2020.
"This is, indeed, a very challenging question," he added.
"The agreement is that we want to organise these Games at the latest in the summer 2021. This is not restricted just to the summer months. All the options are on the table, including the summer 2021."
Cancellation of Tokyo 2020 was considered, and Bach said that was a decision the committee could have taken alone, but he insisted "it was very clear that should not be something the IOC would in any way favour".
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Bach said he could not guarantee all elements of the Olympics would remain as initially planned and spoke of how "sacrifices" and "compromises" will be necessary as a result of the postponement.
He did not know what would happen with the athletes' village, where apartments were set to be sold after the Games this year.
"Quite frankly I cannot tell you what the situation is," Bach added. "This is one of the many thousands of questions that this taskforce will have to address.
"We hope of course, and we will do whatever we can, that there is an Olympic Village - because actually in the village the heart of the Games is usually beating. But we are in an unprecedented situation and have an unprecedented challenge.
"We have to find the best possible solution under the circumstances we are living in."
Asked what the priorities were when compromises are being made, Bach said: "This is like a huge jigsaw puzzle and every piece has to fit. You take out one piece the whole puzzle is destroyed.
"Everything has to come together and everything is important. This is why I really do not envy the members of this taskforce in their work."
He added: "A Games has never been postponed before. We have no blueprint, but we are nevertheless confident we can put a beautiful jigsaw puzzle together and will then in the end have a wonderful Olympic Games."
There has been speculation about how commercial contracts for Tokyo 2020 will be affected by the postponement.
Bach said the IOC has spoken to the major sponsors and been reassured they are supportive of the rescheduled Games.
"What we can see is we have their full support for this decision, and we will now work to implement it," said the IOC chief.
"It is the logical consequence that the sponsors of Olympic Games Tokyo 2020 keep their rights even if the Games are organised in 2021."