US retail giant Wal-Mart has raised its full year earnings outlook after witnessing a surge in first half net sales.

During the first six months of the fiscal, Wal-Mart saw sales rise a total of 10.3% to US$177.4bn. The gains were driven by Wal-Mart's international businesses, where sales increased by 19.3% to $41.2bn. Sam's Club and Wal-Mart US posted more modest gains of 7.8% and 7.6% respectively.

Price leadership, enhanced customer service and operational improvements remained the primary drivers of sales growth worldwide, Wal-Mart said.

Wal-Mart president and CEO Lee Scott said that the retailer was well positioned to benefit from the global economic downturn.

"We have improved customer traffic and ticket and overall sales growth in our markets," Scott commented. "While inflation and higher fuel costs are pressuring suppliers, retailers and customers worldwide, we're confident that Wal-Mart is well-positioned for this economy."

Operating income increased to $10.96bn for the six months, with international again leading gains. International operations saw operating income rise by 17.6% for the period. Wal-Mart US income rose 10.2% while Sam's Club gained only 0.4%.

Earnings per share for the second quarter rose to $0.86 from the previous year's result of $0.75. Wal-Mart therefore increased its full year EPS guidance to a range of $3.43 to $3.50 per share.