Machinery orders sank again in October in a fresh sign that business spending, previously one of the few points of strength in the world's third-largest economy, is stalling as slumping exports bruise investment appetite.

Core machinery orders fell 6.0 percent in October from the previous month, government data showed on Thursday, logging a fourth straight month of declines and dashing expectations for a 0.9 percent increase in a Reuters poll.

The data marked the longest period of month-on-month contraction since a similar stretch to January 2009, and throws up a challenge for policymakers counting on solid business spending to support demand amid a global slowdown.