Total sales volumes decreased 1.8 per cent between December and January - the largest monthly fall since January 2003, when sales dropped 2 per cent.
Clothing, which suffered a 4.4 per cent decline, was the biggest contributor to the slide. Household goods sales tumbled 4.2 per cent and other non-food sales fell 3.7 per cent.
However, the total volume of sales in January was 3.3 per cent higher than in January 2006.
For the three months to January, the unadjusted value of retail sales was 3.9 per cent higher than the same period the year before. The average weekly value of sales in January was£4.4 billion - 2.8 per cent higher than in January last year. Food stores sales increased 3.4 per cent over the year, compared with 1.1 per cent growth for non-food stores.
Barclays business banking director for retail and wholesale Paul Clarke said: 'Following strong sales over Christmas, consumers continued their love affair with the high street by taking advantage of the new year Sales, although it appears their ardour cooled towards the end of the month.
'However, it remains to be seen if the smile on the faces of retailers will last into the spring. Commodity prices have been rising for over a year and with retailers already under pressure on margins, we can expect some prices to increase.'
He added: 'While the retail industry continues to thrive among the strong housing market in London, the picture is varied across the country and across sectors, with some retailers having great success with their online/multichannel operations while other high street retailers struggle. Nevertheless, those that have got their strategy right will continue to flourish.'