Tesco has dumped supplier Silvercrest Foods because of the horse burger scandal and accused the company of failing to follow its specific meat sourcing instructions.

Tesco said the ABP Food Group subsidiary used meat in Tesco own-label frozen burgers that “did not come from the list of approved suppliers we gave them” and also was not from the UK and Ireland “despite our instructions that only beef from the UK and Ireland should be used in our frozen beef burgers”.

“Consequently we have decided not to take products from that supplier in future,” said Tesco group technical director Tim Smith. “We took that decision with regret but the breach of trust is simply too great.”

The Irish government announced over the weekend that tests on raw materials used at Silvercrest showed the horse DNA contamination had come from an imported frozen meat ingredient from Poland. In earlier tests by the Food Safety Authority of Ireland, one Tesco Everyday Value burger made by Silvercrest tested positive for 29.1% horse DNA relative to the beef content.

Smith said Tesco would now introduce comprehensive DNA checks across its meat products. “We have a well-equipped, expert technical team and world-class checks in place but we will not take anything for granted after this incident,” he said. “It has shown that, in spite of our stringent tests, checks and controls there remained a small possibility that something could go wrong and it did. We want to stop it ever happening again, so we are taking action to reduce that possibility still further.

“These checks will set a new standard. It will be a significant investment for Tesco, borne by Tesco. We want to leave customers in no doubt that we will do whatever it takes to ensure the quality of their food and that the food they buy is exactly what the label says it is.”

Silvercrest Foods was not immediately available for comment.

Smith will give evidence on the horse burger scandal to the EFRA cross-party committee of MPs later this afternoon, alongside Iceland’s technical director, Trish Twohig, the FSA as well as farming minister David Heath and public health minister Anna Soubry.