Low-income customers at Wal-Mart appear to be using Christmas gift cards to buy food and other basics rather than using them on discretionary gifts, the largest US retailer said on Thursday, in a telling sign of the economic pressures facing the least well-off US consumers.

Wal-Mart cited lower-than-expected redemptions of gift cards during January as a factor for moribund sales during the month. Sales at stores open at least a year increased by just 0.5 per cent, against its original forecast of 2 per cent growth.