In a widely expected move, the BOJ maintained its short-term interest rate target at minus 0.1 percent and a pledge to guide 10-year government bond yields around zero percent.

The decision on maintaining its interest rate targets was made by an 8-1 vote with board member Goushi Kataoka dissenting on the view additional stimulus was needed to hit the target.

"Inflation expectations are moving sideways recently," the BOJ said in a quarterly report, offering a more optimistic view than three months ago when it said they were moving on a weak note.

BOJ Governor Haruhiko Kuroda will hold a news conference at 3:30 p.m. (0630 GMT) to explain the policy decision.

(Reporting by Leika Kihara, Stanley White, Tetsushi Kajimoto and Minami Funakoshi; Editing by Chang-Ran Kim)