Coates also hit out at the suggestion that the IOC was ploughing ahead with the Games "at all costs" to fulfill lucrative contracts with broadcasters and sponsors.
Nearly 80% of the Japanese public are now opposed to holding the Summer Games as scheduled this year, recent polls show.
The International Olympic Committee (IOC) is working with sports bodies to arrange a July-August window for the postponed Tokyo Olympics in 2021 and hopes to confirm the schedule within a month, Japan's Yomiuri newspaper reported on Thursday. John Coates, the IOC's Coordination Commission chief for Tokyo, told the Yomiuri the Games would have to be held between the tennis Grand Slams of Wimbledon, slated to end in mid-July, and the US Open, which starts in late August.
International Olympic Committee (IOC) vice president John Coates called Brazil's preparations for the 2016 Rio de Janeiro Games "the worst" he has ever seen and critically behind schedule, but warned there is no "plan B" to find another host.
Russia asks World Athletics to postpone decision on possible expulsion.
'With one year to go, there is no clear picture of what shape the simplified Games will take. The situation with COVID-19, both domestically and internationally, is constantly changing.'
The Tokyo Olympics are not contingent on the development of a vaccine for the coronavirus, International Olympic Committee member John Coates said. Australian Coates, the head of the IOC's Coordination Commission for the Olympics, said JMA president Yoshitake Yokokura's comment was an 'opinion'.
The International Olympic Committee has been advised by the World Health Organization that there is no case for contingency plans to cancel or relocate the Tokyo 2020 Olympics over the coronavirus outbreak, the IOC's Coordination Commission head said on Friday.
Tokyo officials have said they intend to put on the Games in 2021 even if the pandemic has not eased substantially.
The International Olympic Commission will not change its decision to move the 2020 marathon to Sapporo to avoid the heat, a top Tokyo Olympics planning official said on Friday, despite pleas from Tokyo's governor to keep the race in the capital.
The Tokyo Olympic games were postponed last year due to the pandemic. The showpiece event will be held from July 23 to August 8, 2021, while the Paralympics will take place from August 24 to September 5, 2021.
The Olympics were due to begin on Friday with an extravagant opening ceremony in the National Stadium but the Games have instead been delayed until July 23, 2021 because of the global COVID-19 pandemic.
'The IOC is actively working with its Japanese partners in the Tokyo 2020 Organising Committee and with the National Olympic Committees on the details of this policy (of flying in additional medical personnel)'
The new schedule means women's softball will kick off competition at 9 a.m. (0000 GMT) in Fukushima on July 21, two days before the Games officially open, with all events taking place a day earlier than the 2020 schedule.
Olympics organisers must replan the Games without running up huge additional costs. IOC President Thomas Bach said his organisation faces several hundred million dollars in supplementary costs.
Rio de Janeiro mayor Eduardo Paes has described Australia's Olympic committee as a "source of aggressions" against Brazil after it banned the team's athletes from visiting the city's favelas during the Games in August. Australia's team chef de mission Kitty Chiller told News Ltd media on Sunday that their Olympians would be barred from going to the urban slums, even on official tours, in accordance with advice from a security expert. "There is still much unfamiliarity about Rio and Brazil," Paes told Brazilian media. "There is a certain dramatisation. And between us, the Australian committee has been a source of aggressions to Brazil." Rio's favelas are among the most violent and crime-ridden areas of the city. Australian Olympic Committee (AOC) president John Coates, a member of the International Olympic Committee's coordination commission, said in April 2014 that Rio's Games preparations were the worst he had ever seen and critically behind schedule. Coates was more generous in a January assessment, however, saying he felt "very positive" about the delivery of the Games.
Plans that had been almost a decade in the making were shredded as the COVID-19 pandemic forced the IOC and Japanese government to take the unprecedented decision to postpone the Olympics for a year.
'I believe there will be some treatment (of coronavirus) by September or October this year. We (India) have to plan ourselves thinking that Olympics will be held.'
The report comes after two members of the Ugandan Olympic delegation tested positive for the coronavirus last month upon arrival in Japan. One tested positive at Narita airport near Tokyo, but the remainder of the team was allowed to travel to a training site.
During his speech, he recalled the role of sport and the Olympic Games to build bridges, bring people together and shape the peace.
The next challenge for Tokyo organisers is developing measures to help prevent a COVID-19 outbreak during the Games and how much the delay will cost Japanese taxpayers.
The COVID-19 pandemic, which has infected over 30 lakh people worldwide, has halted all sports, including badminton, across the globe with even the Tokyo Olympics being pushed to next year. Tennis star Novak Djokovic had recently said he is opposed to a compulsory coronavirus vaccination.
A summary of sports events and sports persons, who made news on Wednesday
It was an extraordinary turnaround for an Olympics that was expected to be held without major issues by a country known for public safety and economic stability. It also revealed a fatal miscalculation by Japanese and IOC officials of public sentiment at a time of heightened fears over the coronavirus.