U.S. manufacturing expanded in December at the fastest pace in close to four years, reinforcing the growing belief that a global economic recovery is under way and perhaps breathing new life into global supply chain activity.

The Institute for Supply Management's (ISM) factory index rose to 55.9, the highest level since April 2006, according to the Tempe, Ariz.-based group. A reading greater than "50" signals expansion.

Economic activity in the manufacturing sector expanded in December for the fifth consecutive month, and the overall economy grew for the eighth consecutive month, according to the supply executives surveyed by ISM.

In a statement, Norbert J. Ore, chair of ISM's Manufacturing Business Survey Committee, called the December report "quite strong" with indexes for new orders and production above 60 percent.

Ore said orders are "benefiting from an excessive de-stocking cycle," noting that inventories have been "too low" for nine consecutive months. Ore said the ISM inventory index reported its lowest reading since its inception 13 years ago, indicating that inventories have reached unsustainably low levels.