Online Christmas shopping sales in the US have risen by a quarter compared to last year, new figures show.

Statistics released by web monitoring firm comScore show that online non-travel retail spending in the US reached £11.7bn during November, representing a 24 per cent increase over last year.

"Online consumer spending during the holiday season continues to surge," said Gian Fulgoni, chairman of comScore Networks.

"Sales were buoyed by strong consumer spending in recent days like 27 November and 28 November, which each saw $608m in spending."

However, the number of visitors to retail sites has grown just 13 per cent, while the total number of visits has grown 12 per cent, demonstrating that consumers are spending about 11 per cent more this year on a per-visit basis.

"In the same way that offline retailers would not think of using only foot traffic counts to gauge in-store sales, savvy online retailers understand that visits to retail websites alone is not a sufficient metric for measuring sales success," said Fulgoni.

"Online site visitation alone does not indicate online sales trends because it does not reflect the rate of visitor-to-buyer conversion nor the value of buyers' shopping baskets.

"It is clear that consumers are increasing their spending per visit to online e-commerce sites."