Tokyo 2020 organizers said Friday they have secured all the venues needed to hold the Olympics next summer, clearing a major hurdle to hosting the event postponed over the coronavirus.

Refunds for ticket holders unable to attend the rescheduled games will begin in late 2020, they added.

Tokyo 2020 reported the progress during an online meeting with the International Olympic Committee, confirming that the delayed Games will use all the venues originally booked for the event.

The 2021 event schedule will also be largely the same as the original, except for small changes made for logistical reasons, said Hidemasa Nakamura, Tokyo 2020 games delivery officer.

"There is still work to be done. But we have arrived at a major milestone," Nakamura told a briefing in Tokyo ahead of the IOC meeting.

With the schedule set, athletes can now begin to prepare in earnest for the delayed Games, due to open on July 23, 2021, said Koji Murofushi, Tokyo 2020 sports director.

"Now athletes aiming to take part in the Tokyo Olympics can set concrete goals to work toward," he said.

The Games' unprecedented delay has caused major logistical headaches and the final price tag for the postponement remains unclear.

Nakamura said organisers were continuing to discuss where to slash costs, adding that changes to "the opening and closing ceremonies are also on the table".

Among the myriad additional costs yet to be tallied will be compensation for businesses that have had their reservations at Olympic venues cancelled to make way for rescheduled events.