In its latest budget update, Tokyo's Olympic organizers project it will cost about ¥5.73 billion ($50.82 million) to build the temporary facilities needed for the baseball, softball and surfing events outside the capital, sources said.

About ¥2.98 billion will be required to upgrade Yokohama Stadium, the main venue for baseball and softball, and about ¥2.75 billion for the surfing venue at Tsurigasaki Beach in Chiba, according to the estimates.

Preliminary cost calculations for these events had been lagging because the venues for new sports to be added to the games had only been finalized by the International Olympic Committee in December.