The head of Tokyo's Olympic organizing committee is concerned that delays in the demolition of the old Olympic stadium will have a negative impact on the 2020 Games and the 2019 Rugby World Cup.

Demolition of the old National Stadium was supposed to begin on Sept. 29 but has been delayed by bidding problems. A new round of bidding has been ordered, further delaying the start of demolition.

Olympic organizing chief Yoshiro Mori, who also serves as president of the Japan Rugby Football Union, told a meeting of city officials he was worried about the delays.

Olympic organizers plan to replace the old stadium with a new 80,000-seat venue that will also host the Rugby World Cup.

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