Supermarket ready meals

But by their saying "Beef, Carrots, Potato, Gravy" they have listed the ingredients - but not the nutritional content?

OK - I see what you mean. It does indeed seem like detailed nutritional labelling is only required where some "health" or nutritional claim is made by the product packaging/advertising even if it looks like many packages carry such detailed labelling where this does not apply. I always assumed that detailed ingredients and nutritional labelling was required on most or all foodstuffs. I guess not after all.

"Gravy" is surely not an ingredient given that it is a compound of various other ingredients - stock, salt, water, additives etc