TOKYO, June 16 (Reuters) - Japan's Nikkei share average fell 2.9 percent to a four-month low on Thursday after the Bank of Japan's decision to keep its policy on hold lifted the yen to near 22-month highs.

The Nikkei slumped to as low as 15,460.28, falling below its April trough.

(Reporting by Hideyuki Sano; Editing by Shri Navaratnam)