Snow Hit Retail Sales In January - Down 0.5%
UK retail sales, excluding fuel, fell 0.5% month-on-month in January with food sales hard hit and snow affecting small grocers.
The Office for National Statistics (ONS) said disruption caused by the weather had a measurable impact.
Food sales tumbled by their biggest monthly margin since May 2011.
Including fuel, sales volumes fell by 0.6%. This follows a downward-revised fall of 0.3% in December, the ONS said.
Ian Geddes, UK head of retail at Deloitte, said: "Today's figures bring into sharp focus the unsettled picture for UK retailers.
"Despite a decent Christmas and tight stock management ensuring effective seasonal discounting, the figures are another blow for the high street."
The official figures follow those released earlier this month by the British Retail Consortium, which found that total retail sales rose by 3% in January.
The ONS figures indicate month-on-month volumes whereas the BRC are year-on-year values and include inflation.
With differences stripped out, they show a broadly similar picture - one of a high street that is flatlining at best.
The pound hit a 6.5-month low against the dollar and gilts extended gains after the sales data was released, wrongfooting market players who had positioned for a better ONS number.
It was the biggest yearly fall in overall retail sales volumes since April 2012 and the biggest consecutive three-month fall in retail sales since March 2010.
The January drop has already prompted fears of Britain entering a so-called triple-dip recession.
Berenberg bank economist Rob Wood said: "This probably brings the question of triple-dip back on the table again.
"If this is the sort of disruption we see from snow, and it's reflected in output in the rest of the economy, then it could be bad news for Q1."
Jens Larsen from RBC added: "There is never a lot of signal in retail sales for consumption demand, and here we have to be particularly careful because of the weather effect.
"But it does look a surprisingly weak number and not all of it can be a weather effect. There is no escaping that this is a weak start to Q1."
According to Deloitte, there are positive signs for retailers, primarily for those who can embrace and exploit technology, which can adversely affect many smaller independents.
Mr Geddes said: "Online and mobile channels have continued to see significant year-on-year growth.
"Perhaps more than ever before, January's results demonstrate the importance of a sophisticated multi-channel strategy.
"Those with effective digital and mobile services have reaped the rewards, whilst those still coming to terms with the online revolution have struggled."