City officials hit back at plan to move event 800km north to Sapporo, saying they were not consulted about the shift

The marathon and walking events at next summer’s Olympic Games could start at 5am to prevent them being moved hundreds of kilometres to Japan’s northernmost island of Hokkaido due to heat concerns.

Government officials in Tokyo toyed with the idea of proposing a new marathon start time of 3am but are now leaning towards 5am, Kyodo news agency said.

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