Meat and fish prices continue to creep up slowly, but generous special offers are keeping rises to a minimum. In the four weeks since the previous survey, just 1.6% has been added to the cost of the basket, but it is now more expensive than it has been for more than a year.

The end of heavy discounting on rump steak at two of the retailers caused a rise of £1.12/kg on the average price, and there were gains in the price of beef steak mince as three retailers increased prices. Rump steak and mince have both now reached their highest prices since the survey began in January 2005.

But pork products still show no signs of upwards inflation, with no gains for own-label sausages and pork chops, and a one-third-off promotion on unsmoked back bacon at Sainsbury's. That comes in spite of calls from pig industry representatives for price increases.

The whole chicken price fell slightly as Asda cut the price of its cheapest chicken to well below the other multiples, while Tesco's price went in the opposite direction.

Cuts in the price of own-label breaded cod by two retailers to a level closer to their rivals brought the average price down 23p/kg.

The basket is now 4.1% more expensive than at this time last year, 16.6% higher than it was two years ago and 9.6% more costly than three years ago.