The head of Wal-Mart Stores said on Wednesday there remained a "lot of stress" in the economy and he did not anticipate a quick end to the recession.

"There's still a lot of stress," Wal-Mart CEO Mike Duke said on NBC's "Today Show."

"It's not a 'V' recession, where we're just going to bounce out and come back," he said.

Duke made the comments a day after a government report showed that sales at U.S. retailers unexpectedly fell 1.1 percent in March, and came after Wal-Mart last week reported a lower-than-expected rise in March sales at U.S. stores open at least a year.

The reports have dimmed hopes that the U.S. recession is close to hitting bottom, and show consumers are unswayed from their new frugal mind-set.

Duke said that by the end of the month, just before traditional paydays, customers are left with only a few dollars to spend.

He said the downturn will lead to a "sustained change" in the way that families live.