Forty percent of all lamb takeaways are 'contaminated' with other meats, according to a survey by consumer group Which?.
The research - timed to coincide with a similar study from the Food Standards Agency - showed that lamb kebabs were particularly affected, with 67% containing chicken and beef.
The watchdog said that, of 60 takeaway lamb curries and lamb kebabs tested in Birmingham and London, 24 were found to contain other meats, while seven were said to contain no lamb at all.
Which? is calling on the government, local authorities and the FSA to crack down on 'food fraud' in order to restore trust following last year's horsemeat scandal.
The continuing nature of food fraud - where products are deliberately mislabelled - shows there is a need for a "renewed effort" in order to force businesses to act honestly about the produce they sell, according to the food regulator.
Andrew Rhodes, chief operating officer at the Food Standards Agency, said:
Prosecutions have taken place against business owners for mislabelling lamb dishes, but the recurring nature of the problem shows there needs to be a renewed effort to tackle this problem. Clearly the message isn't getting through to some businesses.
The further priority testing we have announced today will focus the efforts of enforcement officers and raise awareness amongst food businesses of the action they face for defrauding consumers."
The food watchdog has announced a crackdown on takeaway restaurants selling lamb dishes to customers, when they are in fact using a different meat, like beef or chicken.
The Food Standards Agency (FSA) said priority testing would take place across the UK from the beginning of May.
Businesses selling fake lamb dishes could face prosecution if it is found the meat was deliberately mislabelled.
An FSA review of local authority sampling data, from July to December 2013, found that 43 out of 145 samples of lamb takeaway meals contained meat other than lamb.
None of the dishes tested were found to contain horsemeat, the FSA added.
Severnside Provisions Ltd employs 17 people, and supplies meat to South and South West Wales, and the South West of England, from its base in Newport.
Its operations continue in the run up to Christmas.
Managing Director Anthony O'Sullivan said: "We are having people cancelling orders. I want to reassure people - all of our product is 100 per cent assured. That seized turkey has never been wholesaled."
"We do wholesale turkey, but not process it. It was just a licensing issue. The seized turkey was stored in a part of the building not covered by our licence."
"We had a large batch of turkey condemned and taken away. None of this turkey has made it into the food chain."
"We are looking into how it happened and have already taken steps to make sure it does not happen again."
The Newport company criticised by the Food Standards Agency over turkey butterflies said to have been processed in 'unapproved premises' has told ITV News that none of the turkey product has made it into the food chain, and the issue was simply over storing it in the wrong part of the building.
Severnside Provisions Ltd said it has not processed any turkey, it just wholesales the product.
Managing Director Anthony O'Sullivan said: "It was just a licensing issue. The turkey was stored in a part of the building not covered by our licence."
"None of this turkey has made it into the food chain. There was never any danger to the public."
If you are concerned about a turkey product you have bought, here's the advice from the Food Standards Agency:
- Only turkey butterflies (boneless breast of turkey) affected
- Products have been distributed to retailers in South and Mid Wales, South West and South Central England
- Customers should ask the shop where they bought the product to confirm whether it was processed by Severnside Provisions Ltd
- If so, product should not be eaten
The Food Standards Agency has said that the plant that processed the turkey butterflies "is approved for processing bacon".
But it said the firm had been "processing turkeys in conditions that do not meet the required hygiene standards for food production".
ITV News could not immediately reach Severnside Provisions Ltd for comment.
It is suspected that 12 tonnes of turkey butterflies, processed by Severnside Provisions Ltd at premises in Newport, South Wales were supplied to independent butchers and catering outlets throughout South and Mid Wales, South West and south-central England.
Eight tonnes have so far been retained and prevented from entering the food chain after action by Newport City Council.
There is no evidence at present of any specific risk to public health from consuming this product. However, it is illegal to supply meat from unapproved premises.
Customers have been advised not to eat a batch of turkey butterflies that were produced in "unapproved premises", the food safety watchdog has warned.
Turkey meat was processed by Severnside Provisions Ltd in Newport, South Wales "in conditions that do not meet the required hygiene standards for food production", the Food Standards Agency (FSA) said.
An FSA spokesman said there was no "specific risk to public health from consuming this product" but customers who bought a turkey butterfly processed by the firm are advised not to eat it.
The Food Standards Agency (FSA) tonight said Tesco had issued a recall notice on all Tesco 4 x 110ml packs of chocolate and nut ice cream cones following the two incidents.
Tesco has undertaken a precautionary recall of this product as two individual Tesco chocolate and nut ice cream cones have been found to contain a tablet (for pain relief).
It said the supermarket had recalled all date codes of the product and would be displaying recall notices in stores.