The number of retailers reporting falling sales has risen to its highest level in almost 13 years in the last 12 months.
Some 46 per cent of retailers said their sales slumped in the year to April against 32 per cent who reported rising sales, according to the monthly Distributive Trades Survey by the CBI.
The balance of minus 14 per cent was the biggest year on year tumble since July 1992, when it hit minus 15 per cent. The April figure compared unfavourably with the balance in March of minus nine per cent.
CBI chief economic adviser Ian McCafferty said tough trading conditions were continuing for most retailers despite expectations last month that the position would stabilise.
The ongoing decline in sales was likely to reflect the recent fall in real disposable incomes, higher fuel and utility bills, reduced housing market activity and higher mortgage rates than a year ago, he said.
"These results add further weight to the argument against a premature rise in interest rates," Mr McCafferty said.
There was poor trading in most sectors during the period, particularly by chemists and furniture and carpet retailers, the survey showed.
However, household durable products did relatively well, probably due to sales of technology products.
Booksellers, stationers and grocers were the only others to grow sales.
Sales volumes for wholesalers stabilised during the year to April after weak results in the year to March, although their sales remained below average for the time of year.
Sales in the motor trade continued to fall in the period, in line with March expectations. It was the eleventh successive month in which sales of new vehicles fell year-on-year, whilst sales of parts and accessories were unchanged over the same period. Motor traders expect a slightly steeper decline in sales in the year to May.
Mr McCafferty said: "The figures from the automotive sector are a reminder of the highly competitive sales market which contributed in part to MG Rover's collapse."
John Butler of HSBC said the survey had been reasonably good at picking up the trend in underlying sales and demonstrated that the slowdown in retail spending was showing few signs of stabilising.
Capital Economics' UK economist Vicky Redwood said: "The tone of the survey was in line with the continued bearish reports and profits warnings coming from retailers themselves."
Geoffrey Dicks of RBOS Financial Markets said the survey showed the underlying trend on the high street was poor and the effects of five interest rate increases were increasingly visible.