US retail giant Wal-Mart has reported an 8.8% rise in August sales, but said US comparable store sales rose just 0.5%.

The company posted net sales of US$21.20bn for the four weeks to 27 August, compared to $19.49bn in the year-ago period.

The Wal-Mart Division's sales for the four-week period were $14.30bn, up 7.0% over sales of $13.36bn in the prior year period. Sam's Club sales rose 4.0% to $2.76bn.

Wal-Mart's International Division recorded sales of $4.15bn for the four-week period, up 19.3% over sales of $3.48bn a year earlier.

Total US comparable sales rose 0.5% for August; Wal-Mart comparable sales edged up 0.1%, while Sam's Club comparable sales rose 2.7%.

For the September five-week period, the company has forecast comparative sales growth in the US to be up in the 2-4% range.