The FSA said it received 29 positive results for the seven products which contained undeclared horse meat above one per cent.
The products linked to the positive results are Aldi’s special frozen beef lasagne and special frozen spaghetti Bolognese, the Co-op’s frozen quarter pounder burgers, Findus beef lasagne, Rangeland’s catering burger products and Tesco value frozen burgers and value spaghetti Bolognese.
FSA director of communications Stephen Humphreys said he could "assure" the public that all seven had now been taken off the shelves but that it would likely be "impossible" to ever know the full extent of horse meat mis-labelling.
He said: "What we have in these sets of results is a snapshot of what has been on the market and provided by wholesalers, by caterers, by retailers in the period between January, when this story broke, and now.
"We don't have any reliable information on what might have gone on before January 15."
Ahead of the FSA test results announcement several major retailers said test results on their processed meals had proved negative for horse meat.
Tesco, Sainsbury's, Morrisons, Iceland, Marks and Spencer and the Co-op said no horse meat was found in their products.
Asda withdrew its 500g beef bolognese sauce from shelves yesterday after tests revealed the presence of horse DNA.
The company apologised to customers and said it was taking a "belt-and-braces approach" by removing a further three beef products made by the same supplier, the Greencore plant in Bristol, as a precaution.
The Food Standards Agency (FSA) had asked retailers and suppliers to provide "meaningful results" from tests to detect the presence of horse meat in processed meals labelled as beef.
The FSA said it wanted the food industry to show the food it sells and serves is what it says it is on the label.
Helen Dickinson, director general of the British Retail Consortium, which represents supermarkets, rejected claims that its members were slow to remove products potentially containing horse meat from their shelves.
"Retailers have not been reticent, they have been working hard over the last three weeks since this issue first arose to make sure any problems they do identify they act on quickly," she said.
Pub and hotel group Whitbread has now become the latest company to admit horse DNA had been found in its food, saying today their meat lasagnes and beefburgers had been affected.
The firm, which owns Premier Inn, Beefeater Grill and Brewers Fayre, said the products had been removed from their menus and will not be replaced until further testing has been carried out.
A spokesman said: "We are shocked and disappointed at this failure of the processed meat supply chain. As an industry it is clear we need the supply chain to deliver products to the highest standards of food integrity and quality that we and our customers expect.
"As a responsible business we shall work with the FSA to implement a robust testing regime to avoid this happening in the future. We would like to sincerely apologise to our customers for any concerns or inconvenience that this may cause."
Whitbread said they had sent 30 products to be tested, receiving the results yesterday afternoon.
It has also been confirmed that cottage pies delivered to schools in Lancashire have tested positive for horse meat and that burgers containing it had been supplied to hospitals in Northern Ireland.
The FSA results were being released as police in Wales questioned three men arrested on suspicion of offences under the Fraud Act.
The trio were taken into custody from two plants inspected and temporarily shut down by the FSA on Tuesday.
Sources said Dafydd Raw-Rees, 64, owner of Farmbox Meats near Aberystwyth, was arrested along with a 42-year-old man.
A 63-year-old man was also arrested on suspicion of the same offence at Peter Boddy Slaughterhouse in Todmorden, West Yorkshire.
On Wednesday, owner Mr Boddy, 63, said he had done nothing wrong and insisted the FSA inspection was merely to look at his records, but was last night unavailable for comment.
His firm is also contracted to remove fatally injured horses from the Grand National.
It removes the carcasses of some horses which have been put down during the world famous meeting, Aintree Racecourse, and said it was "confident" no unfit meat had entered the food chain.
The arrests were made by Dyfed-Powys Police in a joint operation with the FSA.
The two plants became the first UK suppliers suspected of passing off horse meat for beef.
Production at both plants was suspended pending the outcome of investigations into claims they supplied and used horse carcasses in meat products purporting to be beef for burgers and kebabs.
Yesterday it emerged a significant amount of horse meat containing the painkiller phenylbutazone - or "bute" - could have been entering the food chain for some time.
Authorities in Britain and France are trying to trace the carcasses of six horses contaminated with bute - which were slaughtered in a UK abattoir and may have entered the human food chain across the Channel.
The drug, which is potentially harmful to human health, was detected in eight horses out of 206 tested by the FSA in the first week of this month.
Two were intercepted and destroyed before leaving the slaughterhouse but the other six were sent to France, where horse meat is commonly eaten.
The FSA yesterday entered three more meat plants in England as part of their investigation.
It came after Peter Boddy slaughterhouse in Todmorden, West Yorkshire, and Farmbox Meats in Llandre in Aberystwyth, West Wales, were raided on Tuesday.
The FSA had also tested products for pork contamination.
FSA chief executive Catherine Brown said: "We tested for horse and pork at this stage and when we review the figures we will be looking at both of those.
"Gross contamination with horse meat is the priority at the moment and that is what we are first concentrating on but we have collected the data and we will look at that."
Ms Brown said the testing process was vital to eradicate horse meat from the UK food chain.
"First, we remain confident that this is the right way to address this issue and get to the bottom of it," she told a press conference in central London.
"It will take some time to complete the process and is costly for the industry.
"But it is industry's responsibility to get this right - not the Government's - and we consider that a comprehensive testing programme at all points of the supply chain and in all sectors is an essential step in addressing this issue.
"Second, the results show that the overwhelming majority of beef products in this country do not contain horse. The examples we have had are totally unacceptable. But they are the exceptions.
"And as this programme of testing and publishing results continues, and as action is taken to tackle this issue in supply chains across Europe, we will reach the point where we can say with confidence that horse meat is no longer illegally entering the UK food chain."
Simon Coveney, Agriculture Minster in the Irish Republic, said agreement had been reached at a European level on new tests for horse DNA and traces of the veterinary drug phenylbutazone, known as bute.
The first round of tests will be carried out by the end of March and results will have to be reported to the European Commission by April 15.
The EC will fund three quarters of the cost of the first month's testing.
"This testing will contribute to a clearer understanding of the situation across Europe," Mr Coveney said.
