A woman wearing a traditional Japanese kimono poses next to the Olympic rings in front of the Japan National Stadium in Tokyo on Wednesday. AFP

The head of the global Olympic movement said on Wednesday the rescheduled Tokyo Games faced "thousands" of logistical and financial problems but could go ahead before summer 2021.

Though most people have assumed the Games will be held around roughly the same July-August timetable as they were planned for this year, International Olympic Committee (IOC) President Thomas Bach said earlier dates in 2021 were possible.

"The agreement is that we want to organise these Games at the latest in the summer 2021," he told a conference call.

"This is not restricted just to the summer months. All the options are on the table including the summer 2021."

The IOC agreed with Japan on Tuesday to the first postponement in the Olympics' 124-year history due to risks from the coronavirus impact.

It was the last major international sporting event of 2020 to be cancelled, with many questioning why a seemingly inevitable decision took so long to make as the coronavirus epidemic raged around the world.

US President Donald Trump on Wednesday praised Japan's decision to delay the Tokyo Olympics over the coronavirus pandemic and indicated he will attend the rescheduled games next year.

"Congratulations to Prime Minister Abe of Japan, and the IOC, on their very wise decision to present the Olympics in 2021," Trump tweeted. "It will be a great success, and I look forward to being there!"

Athletes were sad but largely relieved, given disruption to their training. The decision was a huge blow to Japan, which has invested $12 billion in the run-up, and presents a massive headache to reorganise logistics, funding and sponsorship.

Bach said he could not guarantee all elements of the Games would remain as initially planned. For example, he did not know what would happen with the athletes' village, where apartments were set to be sold after the Games this year.

"This is one of the many thousands of questions this task force will have to address. We hope and we will do whatever we can so that there is an Olympic village, the village is where the heart of the Games beat," he said.

Bach also warned the $12 billion price tag for the Games would rise further, with additional costs for everyone involved.

"Our mission is to organise Games and make dreams of athletes come true," he added. "We have no blueprint but we are confident we can put a beautiful jigsaw puzzle together and in the end have wonderful Olympic Games."

Bach, a 66-year-old German lawyer and former Olympic fencing champion, also said outright cancellation was discussed, even though the IOC had long insisted that was not an option.

"Of course cancellation was discussed and considered like all options on the table, but it was very clear from the beginning that cancellation should not be something the IOC would in any way favour," Bach said.

The IOC has come under heavy criticism in recent weeks from athletes and teams calling for the Games to be postponed and unhappy with the slow decision-making compared to other sports events.

Asked by a German reporter whether he considered resigning over his organisation's handling of the issue, Bach said "No".

In talks with athletes' representatives and national Olympic committees last week, no-one opposed the IOC's stance, he added. After repeatedly insisting the Games were on as scheduled, the IOC at the weekend announced a month of consultations over possible postponement, before seemingly bowing to global pressure for a faster judgement.

The body is due to start talks from Thursday with other global sporting bodies as moving the gigantic Olympics event has a knock-on effect for many other competitions.

"We are in an unprecedented situation. I guess these postponed Olympic Games will need sacrifices, will need compromises by all stakeholders," he added.

'Let us hope'

The Olympic torch relay, due to begin from Fukushima Thursday, has also been postponed but the flame will stay in the area until it is safe to begin.

Organisers have to wrestle with a host of unanswered questions: are the venues still available? What to do with ticket-holders and volunteers? How to fit the Games into a crowded 2021 sporting schedule?

The athlete's village was due to be renovated into more than 4,000 luxury apartments, hundreds of which have already been snapped up. Tens of thousands of hotel rooms will need to be cancelled and rebooked.

"I cannot tell you what the situation is," Bach said when asked about how the postponement might affect the village.

"It's one of the many thousand of questions the taskforce has to address."

Japan and the organising committee were spending $12.6 billion on the Games and experts say they may need to spend around half that again to rearrange the event -- before hopefully recouping the losses when the Olympics are held.

Tokyo 2020 president Yoshiro Mori, an 82-year former prime minister and cancer survivor, pointed to his own health battles as inspiration for the difficult times ahead.

"We have no choice but to have hope. I myself suffered cancer... But I was saved by a new drug. I am here, allowed to live.

"Let us hope for these things."

Agencies