Goshi Hosono, a heavyweight in the largest opposition Democratic Party (DP), has decided to leave the party in an apparent bid to launch a new one, sources close to him said.
Hosono, former acting leader of the party, is set to announce his intention to step down in a meeting of an intraparty group he heads in Tokyo later on Aug. 4.
"It's necessary to create a new organization," he was quoted as telling his aides, hinting that he is aiming to set up a new political party.
However, there are still a certain number of DP legislators who will likely try to persuade Hosono to stay with the DP because of his high name recognition.
Hosono supported Renho in the DP's leadership race in fall last year, and after winning the showdown, Renho appointed Hosono as acting leader. However, Hosono stepped down from the post this past April because of differences with the party leadership.
Hosono, who won a House of Representatives seat for the first time in a 2000 general election, is now serving his sixth term. When the DP's predecessor, the Democratic Party of Japan, was in power from 2009 to 2012, Hosono served as minister in charge of dealing with the Fukushima nuclear crisis and as environment minister.