U.S. wholesale inventories unexpectedly fell in November as wholesale sales outstripped forecasts, a government report showed on Tuesday, suggesting optimism about the sustainability of demand.

The Commerce Department said wholesale inventories fell 0.2 percent to a seasonally adjusted $425.5 billion. Economists polled by Reuters had expected a 1 percent rise in inventories after an October increase that was revised downward slightly to 1.7 percent. It was the first fall in wholesale inventories since December 2009.

Wholesale sales in November rose 1.9 percent to a seasonally adjusted $370.1 billion, well ahead of forecasts for a 1.5 percent increase. October sales were revised upward to a 2.6 percent gain after an initial report of a 2.2 percent rise.

The stronger than expected sales and the fall in inventories implied that demand during the holiday shopping season may have been greater than retailers had anticipated.

The inventory -to-sales ratio, which measures how long it would take to deplete stocks at the current sales pace, also fell in November to 1.15 months, from a downwardly revised 1.17 months in October.

(Reporting by David Lawder; Editing by Neil Stempleman)