Okinawa Gov. Denny Tamaki is set to run for the gubernatorial election expected to take place in September, seeking his second term as the governor of the southern island prefecture, hosting the majority of U.S. military bases in Japan, according to people familiar with the matter.

Tamaki plans to announce his bid after a prefectural assembly session opens on Feb. 15. All Okinawa Kaigi, which comprises political parties and civic groups opposed to a Japan-U.S. plan to relocate a key U.S. military base within the main island, will back him, the people said.

Tamaki revealed his intent to run for re-election to a group of his supporters late last month, according to the people. However, at a news conference Friday, he stopped short of declaring his candidacy, saying he was hoping to do his best until the current term ends and "will think about when I will express my next course of action."