Milk contaminated with illegally high levels of the chemical dioxin has been found on farms in Northern Ireland, it was announced today.

The contamination is thought to come from animal feed imported from the Irish Republic that was responsible for contaminated pork and beef being removed from the shelves just before Christmas.

The Food Standards Agency said the risk to health from drinking the affected milk or eating products made from it was extremely low.

An FSA spokesman said: "Milk from two dairy farms in Northern Ireland has been stopped from entering the food chain following test results that show dioxin levels above legal limits.

"Although breaching regulations, these levels of dioxin are much lower than those found in pork and beef affected by feed contamination last year."