Mayor Tomihisa Taue told the city assembly that Nagasaki would continue to back Hiroshima should they decide to remain in contention for the games, the Kyodo news service reported Saturday.
The two cities, which share the tragic distinction of having been hit by atomic bombs at the end of World War II, had sought to host the games as a statement against nuclear weapons.
The Japanese Olympic Committee last month turned down the Hiroshima-Nagasaki bid on the grounds political statements are not permitted under the Olympic Charter.
In addition, the charter requires that one city alone host the games, Kyodo said.
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