The panel suggested the rowing and canoeing venues be moved some 400 km (250 miles) from Tokyo to three possible sites but the organisers say such adjustments may prove difficult to instigate in time for the 2020 Olympic games.
The panel also revealed the rowing venue, estimated to cost 6.9 billion yen ($67.40 million), now comes in at 49.1 billion yen ($479.59 million).
Any change in the rowing and canoeing venues would require the approval of the International Olympic Committee (IOC) and the World Rowing Federation.
Tokyo has already shifted venues for several events out of the capital, including sailing and basketball, while cycling will take place in Shizuoka, about 200 km (125 miles) west of Tokyo.
(Reporting by Shravanth Vijayakumar in Bengaluru; editing by Amlan Chakraborty)
