The International Council of Shopping Centers said U.S. shoppers lost their momentum in the week ending Saturday due to warm weather and rising gas prices.
"Customers appear to have taken a break as temperatures warmed up and gasoline prices continued to soar," the trade group based in Washington said.
The group said week-to-week sales receipts for retailers fell 2.5 percent, although sales were 2.1 percent higher than the same week of 2011.
Weather Trends Inc. said the average temperature across the country was 1.4 degrees Fahrenheit warmer than the same week a year earlier.
In the Northeast, it was also the third driest week in more than 21 years, comparing last week to the same week of previous years.
Dry, warm weather, meant there was strong demand "for outdoor categories, like tailgating supplies."
But shoppers may have felt pinched by higher gasoline prices.
The U.S. Energy Information Administration said the average gas price has risen by 52.2 cents over the past 11 weeks with the price up 3.1 percent in the most recent week, reaching $3.878 per gallon as a national average on Monday.
