Democratic Party of Japan lawmaker Azuma Konno submitted a letter of resignation to House of Representatives Speaker Yohei Kono on Thursday, a day after the Sendai High Court invalidated his victory in the 2003 general election.
Konno met DPJ President Katsuya Okada earlier Thursday to express his intention to give up the Lower House seat representing Miyagi Prefecture's No. 1 constituency.
If the chamber approves Konno's resignation, a by-election for the electoral district will be held Oct. 23.
On Wednesday, the high court invalidated Konno's election win because one of his campaign managers had been found guilty of illegal electioneering for the November 2003 polls.