British retail sales jumped 1.1 percent in July from the level in June as a heatwave fuelled spending on food, drinks and summer clothing, official data showed on Thursday.
July's figure beat market expectations for an increase of 0.7 percent according to a survey by Dow Jones Newswires.
Retail sales -- an important indicator of consumer confidence -- grew by 3.0 percent in July compared with one year earlier, the Office for National Statistics (ONS) added in a statement.
It was the steepest annual rise since January 2011. Analysts had forecast a smaller year-on-year gain of 2.5 percent.
"Feedback from supermarkets suggested that the sunny weather boosted sales across a range of products including food, alcohol, clothing and outdoor items," the ONS said.
The data builds on a number of recent releases showing improvement across all sectors of Britain's economy.
"With consumer confidence on the rise and continued growth in employment, the retail sector looks set fair for the third quarter, even as the boost from the weather fades," Martin Beck of the Capital Economics research group said in reaction to the retail sales figures.
"However, with real pay set to continue falling into next year and households eating into their savings, the resources to sustain growth in sales still look lacking," he cautioned.
Last month, Britain sweltered in its first prolonged heatwave for seven years as temperatures topped 30C (86F) for a number of days in a row.
The nation's economy has meanwhile experienced an upturn in fortunes, with gross domestic product growth of 0.6 percent in the second quarter, double the rate during the first three months of the year.