Wal-Mart Stores Inc. on Thursday reported lower-than-expected quarterly sales at established U.S. stores, hurt by declining food prices and warm weather that reduced demand for winter clothes and other seasonal items.

Shares of Wal-Mart, the world's largest retailer, fell 4.3 percent as investors shrugged off strong online sales growth and a smaller-than-expected decline in earnings.

The company also raised the low end of its fiscal-year profit forecast, in line with Target Corp and other rivals that expressed optimism ahead of the holiday shopping season.

Wal-Mart said it did not expect last week's U.S. presidential election to have a significant effect on holiday spending plans.

"It's way too early to speculate on anything that might happen with the president-elect," Chief Financial Officer Brett Biggs told Reuters.

Biggs said declining prices for eggs and other important products for a food retailer remained challenging, and unseasonably warm weather hurt sales in the back half of the quarter.

Wal-Mart's sales at U.S. stores open at least a year rose 1.2 percent, excluding fuel price fluctuations, in the third quarter ended on Oct. 31. That was weaker than market expectations of a 1.3 percent rise, according to research firm Consensus Metrix.

Comparable food sales fell 1.5 percent in the third quarter, versus a 1 percent decrease in the second quarter.

U.S. store visits rose 0.7 percent, slowing from increases of 1.7 percent a year earlier and 1.2 percent in the second quarter.

Net income attributable to Wal-Mart fell more than 8 percent to $3.03 billion, or 98 cents per share, from $3.3 billion, or $1.03 per share, a year earlier. Analysts on average expected 96 cents per share, according to Thomson Reuters I/B/E/S.

Net sales rose 0.5 percent to $117.2 billion.

Online sales increased 20.6 percent, accelerating from the previous quarter. That business added 50 basis points to third-quarter comparable sales, its biggest contribution to date.

To try to narrow the gap with online leader Amazon.com Inc and increase its dominance in retailing, Wal-Mart has invested heavily in e-commerce, acquiring startup Jet.com in August for $3 billion.

"The U.S. (e-commerce) results were stronger than those in our key international markets, driven by our marketplace offering ... as well as a contribution from Jet.com," Chief Executive Officer Doug McMillon said.

International sales fell 4.8 percent, hurt by a strong dollar and continued weakness in the UK market, but they were up 2.4 percent on a currency-neutral basis.

At Wednesday's close, Wal-Mart's shares had risen more than 16 percent since the start of the year.