The Bank of Japan on Wednesday revised its view of the economy in its monthly report, saying growth is "slowing mainly due to the effects of high energy and materials prices."

Touching on weaker business sentiment and capital spending, the April report represents a more cautious stance by the BOJ on domestic economic conditions, as it deleted a phrase used between July 2006 and March that the economy is "expanding moderately."

The central bank also became more pessimistic about the future outlook, ditching the word "expanding" that had been used since May 2006.