The recall is thought to be the biggest of its kind in British retail history and resulted in millions of individual items being removed from shelves.

It was sparked by the discovery of Sudan 1 in a batch of chilli powder used to make a large consignment of Crosse and Blackwell Worcester Sauce. That sauce, in turn, was added as an ingredient in a host of other products. The FSA said Premier Foods, makers of Crosse and Blackwell Worcester Sauce, first alerted it late on February 7 but did not provide confirmation of the test results until February 10.

Checked for accuracy

A spokesman claims it was not until the following day - February 11 - they were told more than one product were affected. The FSA said it received a list of the companies last Monday, February 14, but a widespread recall could not be announced until the products concerned were known and checked for accuracy.

The updated list includes two types of sausages from Morrisons, Pot Noodles, soups and a ready-made Hot Pot from Waitrose, a Weightwatchers Shepherds Pie and Worcester Sauce-flavoured crisps from Walkers. There are also a number of products supplied by the food company McCormick, including several of its Schwartz brand of seasonings.

Further products to be withdrawn

In addition, there are products made for Sainsbury's and dressings for fast food chain McDonald's. Three products sold under the Aunt Bessie brand are on the list along with four pizzas from Waitrose and a Chicago Town Pizza, from Canterbury Foods.

Sudan 1 is a dye that should not be added to food and is banned in the UK and across the EU. All chilli powder imported to the UK since July 2003 has to be certified as free from Sudan 1. The FSA and local authorities randomly test more than 1,000 consignments of imported chilli powder a year.
The rogue batch used by Premier Foods came into the country in 2002 - before the rules came into force. FSA chief executive Jon Bell warned that further products may have to be withdrawn over the coming days.

"I think there is a very strong chance that we will be having to make further announcements," he told the BBC. "The information is still coming in. More than 300 manufacturers and retailers have been involved in this problem so obviously the extent of the products is very large indeed."

Conservative health spokesman Chris Grayling complained that the FSA had been too slow in issuing the original product recall last Friday. He told the BBC: "I think it is all the more regrettable that consumers were left for a period of up to 10 days still buying these products, unaware that there was an issue.

"My understanding is that some of the supermarket chains started to take products off the shelf several days ago before the FSA made its first announcement. "They clearly knew something was wrong. They clearly had been given guidance that they needed to take action. I think that was the time at which consumers should start to have been given information about the issue."

Dr Bell insisted that they had moved as swiftly as they could. He said: "It was clear that the information we put out had to be sensible for people. It had to be something they could act on.

"Until last thing on Thursday, we did not have anything like a reasonable list to put out. We were still waiting for information from the manufacturers and retailers."