BEIJING (BLOOMBERG) - Researchers at China's top economic planner called for further monetary easing this year to help lower business costs and boost investment.

In a rare public comment on monetary policy, researchers at the National Development and Reform Commission said interest rates and the required reserve ratio for banks should be cut when appropriate, according to a statement on the commission's website on Wednesday.

The research office is an advisory body of the commission - the main government agency for economic planning and reform - and doesn't have direct power to set policy. The NDRC usually doesn't make public commentary on monetary policy, which is under the purview of the central bank.

Researchers also called for implementing "proactive" fiscal policy and making investment more effective amid downward pressure on spending. China should encourage private firms to raise money by selling bonds, keep pressing to remove excess capacity, promote healthy property investment and keep reducing excess inventories of housing, the NDRC researchers said.