While Rio Olympic Games organisers are under immense pressure to finish preparations before August 5, their Tokyo counterparts are already facing skyrocketing costs for an event four years away.
Tokyo 2020 organising committee president Yoshiro Mori acknowledged at an executive board meeting this week the cost of building seven temporary venues for the Olympics had surged to an estimated $US2.6 billion ($A3.45 billion), up from an initial estimate of $US690 million ($A919.45 million).
Mori said the original figures were the result of sloppy calculations which he blamed on the Tokyo metropolitan government and the Japanese Olympic Committee.
The organising committee hasn't disclosed an official estimate of the overall costs but has acknowledged it will be considerably higher than the $US3.5 billion ($A4.65 billion) originally forecast.
