Wal-Mart Stores Inc is expecting a late Christmas as consumers continue to carefully manage spending, CEO Mike Duke said at an investor conference on Thursday.

Duke said shoppers are keeping a watchful eye on prices and are less likely than before to stock up on items or to purchase lower-quality throw-away items.

Consumer spending, an important driver of the U.S. economy, has fallen off sharply during what has become the longest and deepest recession since the Great Depression.

This is the new normal. This is not something that is going to change, Duke said at the Goldman Sachs Global Retail Conference.

Duke said the world's largest retailer is prepared for the upcoming winter holidays, but that he expects it will be a late Christmas.

The chief executive said Wal-Mart still has opportunity for growth in many U.S. markets but that investors should not expect to see any significant increase in long-term margins.

(Reporting by Lisa Baertlein; editing by Gunna Dickson)