Online retailer Amazon.com Inc reported its best holiday sales season yet, even as sales and traffic at U.S. store chains were the weakest in decades.

Analysts have pointed to Amazon as a rare bright spot in this year's holiday shopping season due to its scale and flexibility, as retailers try to outdo each other with deep discounts to lure consumers during a recession.

Online sales were also helped by winter storms that hit large sections of the United States on the last major shopping weekend before Christmas.

In a release titled "Amazon.com's 14th holiday season is best ever," the company said more than 6.3 million items were ordered on its site worldwide for the peak shopping day of Dec. 15, amounting to 72.9 items ordered per second. On its peak day, it shipped more than 5.6 million units.

However, the company gave no financial details regarding the sales, such as how its margins fared with the discounts seen across the retail sector.

Stifel Nicolaus analyst Scott Devitt said Amazon's day of peak orders represented a 17% rise from a year ago, while its peak shipments represented an increase of 44%.

Amazon shipped merchandise to more than 210 countries, and said it shipped more than 99% of orders on time for holiday deadlines.