Delays and rising costs have led to reports that the planned retractable roof might not be installed until after the Games, and even that the Stadium might not be ready in time for the 2019 Rugby World Cup.

Officials insist, however, that this is not the case and that Tokyo has no intention to scrap the existing design and start from square one again.

Japan is consulting with the company of British-Iraqi architect Zaha Hadid on a design aimed at lowering costs, according to Education Minister Hakubun Shimomura, with the final decision and contract expected at the start of July.

"At this point we expect that a contract will be concluded at the start of July, but we're still exploring cost cuts and revisions, and if a better plan emerges later the contract could also slip to later," Shimomura said.

"The absolute priority is that the stadium must be finished by the spring of 2019, and then that costs be cut."

Last month, Tokyo Governor Yoichi Masuzoe branded a proposed 58 billion yen (£31 million/$48 million/€44 million) bill towards the cost of constructing the Stadium as "ridiculous".

Despite the cuts to save money, Masuzoe was angry at the figure quoted by Shimomura, which the Tokyo Metropolitan Government would have to pay.

Earlier this week, International Olympic Committee President Thomas Bach urged Japanese leaders to resolve issues surrounding the stadium as officials unveiled further venue changes expected to bring overall savings to $1.7 billion (£1.1 billion/€1.5 bllion).

Bach used the occasion of the latest progress report by Tokyo 2020 to the IOC’s Executive Board in Lausanne to express concerns that continued adverse media reports might cast a shadow over preparations for the Games.

Addressing the media after making their report, Yoshirō Mori, Tokyo 2020 President, and Toshirō Mutō, the chief executive, set out a new series of venue changes affecting seven sports.

"Bidding for the Olympics was something that Tokyo pushed for, as was advancing that bid,” said Mutō.

“The Governors have changed, that is true, but the bid and accepting the Games has not.

"This is certainly something that Masuzoe knew when he ran for Governor and won election."

Mori claims to have received assurances from Shimomura that Japan has no plans to start again from scratch.

"It would be even more delayed, and this would draw international criticism too," he said.  

"So the design will be respected but costs will be cut as much as possible, and it will definitely be finished by 2019, before the Rugby World Cup.

“That's what he said, and I told him to carry on."


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