New orders received by U.S. factories rose more-than-expected in September to post their largest gain in eight months, according to a report on Wednesday that offered more evidence manufacturing continued to expand.

The Commerce Department said orders for manufactured goods increased 2.1% after being flat in August.

Economists polled by Reuters had forecast factory orders rebounding 1.6% in September from a previously reported 0.5% fall in August.

There have been fears that manufacturing, which is leading the economy's sluggish recovery from its longest recession since the 1930s, was slowing sharply, but these concerns continue to be allayed by both regional and national factory surveys.

Data this week showed the Institute for Supply Management's index of national factory activity rose in October to its highest level since May.

In September, orders excluding transportation rose 0.4% after a 1.3% increase in August, the Commerce Department said.

But orders for non-defense capital goods excluding aircraft, seen as a measure of business confidence, slipped 0.2% after increasing 5.1% in August.

Unfilled orders at U.S. factories increased 1.0% in September, the largest rise since March 2008, after a 0.2% gain in August.

Shipments rose 0.4% in September after a small decline in August, while inventories for manufactured durable goods were up for the ninth successive month. That left the inventories-to-shipment ratio, a measure of how long it would take to deplete current stocks, unchanged at 1.27 months' worth.

The department revised durable goods orders for September to show a 3.5% increase rather than the previously reported 3.3% gain.

Excluding transportation, orders for durable goods fell a smaller 0.4% in September instead of 0.8%.