As Nippon Ishin no Kai (Japan Restoration Party) gears up for this summer's Upper House election, its relationship with New Komeito, especially over constitutional revision, has come under increased pressure.

Last week, Nippon Ishin unveiled its basic policy outline for the campaign. At the top of the list was revision of Article 96 of the Constitution, which requires constitutional amendments be passed by a two-thirds majority in both Diet chambers.

Like Prime Minister Shinzo Abe, who heads the ruling Liberal Democratic Party, Nippon Ishin supports changing the requirement to a simple majority in both houses. Party leader Shintaro Ishihara has aggressively pushed for this revision because, like Abe, he sees it as the main roadblock to revising Article 9, the war-renouncing clause. Buddhist-backed New Komeito opposes revising Article 9.