January same-store sales at Wal-Mart Stores exceeded expectations as customers continued to flock to its stores in search of bargains.

"Our sales results were driven by a continuation of gains in customer traffic," said Eduardo Castro-Wright, Wal-Mart Stores' vice chairman.

Net sales for the four weeks to 30 January rose 1.8% to $27.7bn, boosted by a 6.1% jump in sales at its Walmart US stores to $17.96bn.

Sam's Club fell 0.8% to $3.1bn, and international sales were down 7.3% to $6.6bn as fluctuating foreign exchange rates took their toll. On a constant currency basis, Wal-Mart said, international sales rose 11.0% in January.

US same-store sales excluding petrol at the country's largest retailer rose 2.1% last month.

US revenues were driven by demand for grocery and health and wellness products, the company said, but did not reveal details of apparel sales.

In the UK, however, general merchandise and apparel sales at its Asda stores "were ahead of expectations despite a toughening economic environment."

Looking ahead, Wal-Mart is to start providing quarterly rather than monthly guidance as volatile times make consumer swings "more difficult to predict."

US comparable sales without fuel in the three months to 1 May are expected to increase between 1% and 3%.