Yukio Hatoyama announced Wednesday he will seek re-election as head of the opposition Democratic Party of Japan in a party presidency race to be held Sept. 23.

"I have decided once again (to run for) the party leadership," said Hatoyama, who has led the DPJ since 1999.

Hatoyama's predecessor, Naoto Kan, who currently supports him as the party's secretary general, has also announced that he will vie for the leadership in the September race.

Takahiro Yokomichi, a former deputy DPJ chief, announced his candidacy for the race Tuesday. Four junior DPJ lawmakers have also indicated their plans to run.

Hatoyama said the party election marks the end of his partnership with Kan, adding he will try to put more of his own color into the party leadership if elected.