The Bank of Japan Policy Board left its monetary policy intact Tuesday, though it moved to review a program to buy asset-backed securities from financial markets.

BOJ Gov. Toshihiko Fukui asked bank staff to supply fresh ideas on the ABS purchase program -- which the BOJ launched in July with a target of up to 1 trillion yen -- at a Policy Board meeting scheduled for January, the central bank said.

The move represents part of efforts to help small and midsize companies raise funds.

Market participants said the conditions under which the central bank buys ABS are too tight.

It has not bought as much as planned due to the popularity of ABS, whose yields are higher than those of other financial instruments such as government bonds, they added.

The nine-member Policy Board decided unanimously to keep its target for the outstanding balance of deposits in current accounts held by private financial institutions at the central bank in a range of 27 trillion yen to 32 trillion yen.