The company apologised and said it has "never knowingly bought, handled or supplied equine meat products".
A statement continued: "While extensive and thorough safety checks are conducted on all meat products, the industry does not routinely DNA test meat products for species.
"As a result of this incident we are implementing a new testing regime for meat products which will include DNA analysis.
"Should our own testing prove positive, we are also considering our options in respect of the two suppliers concerned. It is vital that the integrity of the supply chain is assured and we are committed to restoring consumer confidence."
It comes after the Food Safety Authority of Ireland (FSAI) revealed that scientific tests found traces of horse DNA in frozen burgers on sale in some of the UK and Ireland's leading supermarkets.
The survey uncovered low levels of the DNA in most products, which were sold in Tesco, Lidl, Aldi, Iceland and Dunnes Stores.
However it showed that the Tesco's Everyday Value Beef Burgers, which were tested by the FSAI, contained about 29% of horse meat relative to beef content. They were also tested positive for pig meat and have been sold in Tesco stores in Ireland and the UK.
The retailers have told food safety chiefs they removed all implicated products from their shelves.
We are aware that investigations are ongoing to ascertain how or why horsemeat was used in the products. This investigation includes tracing back the meat used to make the burgers.
Food Standards Agency in Northern Ireland
The Food Standards Agency in Northern Ireland have confirmed that they are working with the authorities in the Republic.
"It is legal to slaughter and sell horsemeat in the UK, provided it is from an approved abattoir and the meat must carry the stamp declaring it is fit for human consumption," a statement read.
The burgers were produced by Liffey Meats and Silvercrest Foods in Ireland and one UK plant, Dalepak Hambleton.
Silvercrest, a subsidiary of ABP Foods, said that it has never purchased or traded in equine products. The firm are now pulling products from sale and replacing them with new lines.
"Following tests carried out by the Food Safety Authority of Ireland, we have been alerted to frozen beefburgers which contain porcine and equine DNA," said a spokesman.
"Although the products pose no risk to public health, Silvercrest has taken immediate action to isolate, withdraw and replace all suspect product.
"Silvercrest has never purchased or traded in equine product and has launched a full-scale investigation into two continental European third party suppliers who are the suspected source of the product in question."
The FSAI surveyed 27 beef burger products with best before dates from last June to March 2014 with 10 of the 27 products - 37% - testing positive for horse DNA and 85% testing positive for pig DNA.
Some 31 beef meal products, such as cottage pie, beef curry pie and lasagne, were also tested - with 21 found to be positive for pig DNA. All tested negative for horsemeat.
The FSAI survey also found traces of horse DNA in batches of raw ingredients, including some imported from the Netherlands and Spain.
Professor Alan Reilly, chief executive of the FSAI, said there was no health risk - but admitted no reasonable explanation for the presence of horsemeat was found.
"Whilst there is a plausible explanation for the presence of pig DNA in these products due to the fact that meat from different animals is processed in the same meat plants, there is no clear explanation at this time for the presence of horse DNA in products emanating from meat plants that do not use horse meat in their production process.
"In Ireland, it is not in our culture to eat horse meat and therefore we do not expect to find it in a burger."
Prof Reilly said traces of other meats would be unacceptable for people who may not eat certain food on religious grounds.
Tim Smith, group technical director at Tesco, apologised on behalf of the major supermarket chain.
"We will not tolerate any compromise in the quality of the food we sell. The presence of illegal meat in our products is extremely serious."
Lidl said it has taken the decision to remove all implicated products from sale pending a full investigation.
"A refund will be provided to customers who wish to return affected products," said a spokesman.
As we are now in a global food supply chain the chances of such events occurring have increased markedly.
Queen's Professor Chris Elliott
Professor Chris Elliott, Director of the Institute for Global Food Security at Queen's University Belfast, said the findings uncovered an issue about food integrity and thankfully, not safety.
"The substitution of low quality, low value materials for the true foodstuff has plagued food production for centuries.
"While retailers operate wide ranging audit systems to verify that their supply chains are robust there must be scientific verification that these systems are working. This might seem a simple solution but it is far from that."
Prof Elliott added that the costs involved in undertaking high-level verification will ultimately be passed to the consumer.
"However, I believe this is a price worth paying to ensure what we eat is what we think we have purchased."
Agriculture Minister Michelle O'Neill said she supports the efforts of both the FSAI and the FSA to identify how equine DNA product has been incorporated in these products.
"However, I have no reason to believe that this is other than an isolated instance or that there are issues with beef processing in the north. I understand associated product has been withdrawn from supermarket shelves in the north."
The Sinn Féin minister added: "We have an excellent beef processing industry, which meets the highest standards of hygiene, traceability and quality. It is founded on the long tradition in the north of grass fed beef from identified family owned farms."