Both proponents and opponents of revising the Constitution held rallies and meetings Monday in Tokyo to mark the 57th anniversary since it came into force.
While opinion polls show an increasing number of people support revision, about 5,000 citizens and some politicians took part in an event at Tokyo's Hibiya Park to voice opposition to changing the Constitution.
Mizuho Fukushima, head of the Social Democratic Party, said at the event, "Moves to amend the Constitution will accelerate this year. Let us make today the first step to stop the revision."
A citizens' group advocating constitutional revision meanwhile held a meeting at a public hall in Chiyoda Ward.
Kazuo Aichi, former head of the Defense Agency, told the gathering that the question now is not whether to revise the Constitution, but what kind of changes should be made.
With your current subscription plan you can comment on stories. However, before writing your first comment, please create a display name in the Profile section of your subscriber account page.