Britain's retail sales volume increased by 1.8 percent year on year in October, but dropped 0.7 percent on a monthly basis, said the Office for National Statistics (ONS) on Thursday.
The fall in retail sales on the monthly base was unexpected as markets have previously expected a 0.2-percent growth.
Sales volume of textiles, clothing and footwear dropped 0.4 percent year on year, but up 0.7 percent in value, said the ONS.
However, online sales have been growing solidly, and at a faster pace than retail sales in recent years. The proportion of online sales in October increased by 1.1 percent compared with October last year, and accounted for 10.5 percent of all retail sales.
The ONS said the feedback from retailers suggested online specific promotions were a contributing factor to the yearly retail sales increase.
The annual increase in the prices of goods sold in the retail industry slowed from 0.9 percent in September to 0.7 percent in October.
The latest figures from the British Retail Consortium (BRC) also suggested a pickup in British retail sales last month as Christmas approaches with total sales increasing 2.6 percent in value compared with the same period last year, and up from 2.4 percent growth in September.
British retail sector generates 5 percent of the GDP in Britain, with sales exceeding 311 billion pounds (about 498 billion U.S. dollars) in 2012.