The National Farmers' Union said today that supermarkets only have themselves to blame for the horsemeat scandal - for putting price pressure on suppliers.
Farmers now think they have an opportunity to negotiate new deals with the supermarkets.
ITV News Special Correspondent Rageh Omaar reports:
Supermarkets must sell more British products that consumers want and stop scouring the world for the cheapest food they can find, the National Farmers' Union (NFU) demanded in the wake of the horsemeat scandal.
NFU president Peter Kendall said there was "real shock" that consumers have been deceived over what was actually in the meat they had bought.
Speaking at the NFU's annual conference today, Mr Kendall called on retailers to back British farmers and growers.
"We now need supermarkets to stop scouring the world for the cheapest products they can find and start sourcing high quality, traceable product from farmers here at home", he said, adding, "It's not as if it's nuts and bolts, pots and pans or mobile phones - this is our food".
Tesco has emailed its customers to announce its "new commitments" amid the horsemeat scandal.
The email from CEO Philip Clarke states, "Today I make you a promise. Tesco is going to bring the food we sell closer to home. We're going to make how we source our food simpler, more transparent and shorter, and we will build better relationships with our nation's farmers".
Mr Clarke announced all fresh chickens sold in Tesco will come from UK farms from July and that the retailer will move "over time" to ensure all its chicken products - fresh and frozen - will come from British suppliers.
"Everyone in the food industry has a big job ahead to win back your trust. But I am determined to lead the way, by changing the way Tesco sources food for the better", he states.
The email also links to a newly launched Tesco Food News website which he says will "keep you informed on our progress".
"Over time, it will allow you to see where the food you are eating comes from, how it was produced and who produced it", he adds.
Cardiff, Pembrokeshire and Bridgend Councils have withdrawn beef products supplied by Welsh Bros Foods following reports a sample of its frozen minced beef tested positive for horsemeat.
Cardiff Council said it removed the products from its schools, leisure centres and care homes "as a precaution", which was echoed by both Pembrokeshire and Bridgend Councils.
Environment Secretary Owen Paterson told the National Farmers' Union's annual conference that food business operators need to "get out there and win back the confidence of their customers" following the horsemeat scandal.
Mr Paterson said it was the "primary responsibility" of these businesses to ensure food is of the right quality and correctly labelled before it is sold.
He told the audience, "It is totally unacceptable that anyone should buy something labelled beef and end up with horsemeat. That is fraud".
"I am determined that this criminal activity should be stopped and that anyone who has defrauded the customer must feel the full force of law", he added.
Tesco today announced it would be sourcing more meat from UK producers, as supermarkets came under pressure to sell more British food in the wake of the horsemeat scandal.
The supermarket giant's chief executive Philip Clarke told the National Farmers' Union annual conference:
Where it is reasonable to do so, we will source from British producers.
As a first step I announce that from July all of our fresh chicken must come from UK farmers. No exceptions.
And we will move over time to make sure all our chicken in all our products, fresh or frozen, is from the British Isles.
Welsh Bros Foods says it is 'deeply shocked' that a sample of its frozen minced beef has reportedly tested positive for horsemeat.
Welsh Bros Foods regrets to announce that late yesterday afternoon we were informed that a formal sample of our frozen free flow minced beef has been reported to have potentially tested positive for above 1% horse meat. We have not as yet had formal confirmation on this result; however, we have taken the decision to notify our customers of this issue immediately, and issue a withdraw notice for this product.
Welsh Bros Foods are deeply shocked by this development and are working with all relevant authorities.
The firm said the affected batch was produced nearly three months ago and other samples have reportedly tested negative for horsemeat, adding: "We therefore believe at this stage that this is an isolated incident."
Following the Environment Secretary, Owen Paterson announcing badger cull plans, protesters have gathered outside the ICC in Birmingham where the NFU conference is taking place.
Pembrokeshire County Council has withdrawn mince from its menus after being told a batch of frozen minced beef has potentially tested positive for horsemeat.
The mince was supplied by Welsh Bros Foods of Newport, Gwent, and was used by the council for schools, day centres and residential homes.
The council says it has also been made aware that frozen beef products supplied to Sodexo – a company providing catering services to the authority's privately-financed initiative school in Pembroke Dock – has tested positive for horsemeat.
Sodexo has withdrawn all frozen beef products from its UK catering operations.
Secretary of State at Defra, Owen Paterson, MP for North Shropshire, says sale of horse meat as beef was totally unacceptable.
He told the NFU conference in Birmingham.
"I am determined this criminal activity should be stopped."