Budget supermarket Aldi has become the latest company to remove frozen ready meals from its shelves as a procaution, as the horse meat scandal afflicting the food industry continues to roll on.

An Aldi spokesman said on Friday: "Following an alert from our French supplier, Comigel, Aldi immediately withdrew its Today's Special Frozen Beef Lasagne and Today's Special Frozen Spaghetti Bolognese from stores as a precautionary measure.

"Comigel had flagged concerns and we are completing our own investigations. The products will remain withdrawn from sale until we are confident that the meat content complies with the specification presented to us.

"We will continue to refund consumers who return the packaged products to our stores and follow Food Standards Agency (FSA) guidelines on this matter."

Many of the UK's supermarkets are now investigating their meat products and suppliers after traces of horse meat were first spotted in beef burgers sold by Tesco last month.

The latest news arrives after manufacturer Findus found some of its beef lasagnes contained up to 100% horse meat, and the inclusion of horse meat in Findus meals may have been going on for at least six months.

Labour MP Tom Watson said on Friday he had obtained a letter from the company to retailers warning that a French-based supplier told it on 2 February that raw materials delivered to it since 1 August 2012 were "likely to be non-conform and consequently the labelling on finished products is incorrect".

The letter, which Mr Watson said was sent to retailers on Monday, added: "The supplier has asked us to withdraw the raw material batches."

Tesco confirmed to Press Association it was informed of a product withdrawal by Findus on Monday but did not give any more details.

How much further can the scandal go?

Speaking on Daybreak on Friday, shadow environment secretary Mary Creagh talked about her concerns for the wider food market, and predicted further scandals were to come.

"My big concern is about what's lurking in corner shops, and what's lurking in the fridges and freezers of hospitals, prisons and school canteens as well," she said.

"There's now evidence of widespread criminal activity, I believe, with adulterated, fraudulent meat being passed off as beef. It's completely unacceptable."

Creagh also criticised ministers for not getting involved enough with the supermarket investigations.

"I find it astonishing that ministers have met just once with the supermarkets, and that the secretary of state hasn't actually had any meetings at all. I find it quite extraordinary.

"We've got to get transparency into this. We've got to stop the food processors drip feeding this stuff out - that is what's killing consumer confidence. We've got great farmers producing a great beef product, and the confidence in the industry is being knocked and putting jobs at risk."