Former Prime Minister Yasuhiro Nakasone announced he will retire from politics after the Liberal Democratic Party decided Monday not to include him in a party proportional representation list for the upcoming general election.

The 85-year-old Nakasone was dropped from the LDP's official list of candidates for the Nov. 9 election in line with a rule that candidates 73 or older will not be on the party's proportional representation ticket.

Nakasone told a news conference he will not run in the Lower House election from a single-seat constituency. Asked why, he said: "It will mean that I will have to run against an incumbent LDP member. I don't want to cause any trouble."