Japan's government decided in a Cabinet meeting on Tuesday to convene an extraordinary session of the Diet on October 4 to elect the country's next prime minister.
This means the next Lower House election will be held after the legislators' terms end on October 21.
The public office election law stipulates that if the Diet convenes, a Lower House election taking place due to the end of the legislators' terms must be held between 24 and 30 days from the end of the Diet session.
If a general election takes place due to a dissolution of the chamber and voting is carried out on a Sunday as is customary, at least 12 days would be necessary for campaigning.
The internal affairs ministry says if the Lower House election is held after the legislators' terms expire, it would be the first such case in the history of postwar Japan.