The Bank of Japan kept monetary policy steady on Friday in a sign that a first-quarter economic slump did not change the central bank's view that growth will pick up late this year when the wounds from the devastating earthquake begin to heal.

In a surprise move, Deputy Governor Kiyohiko Nishimura dropped his proposal to loosen policy further with an expansion of the central bank's asset-buying scheme. He made such a proposal last month but was voted down by an 8-to-1 margin.