Nine Northern Ireland farms have used the same contaminated feed which has led to a recall of all pig products processed in the Republic.
Agriculture Minister Michelle Gildernew said restrictions had been placed on the farms on Friday.
The UK’s Food Standards Agency has said pork from the Irish Republic and Northern Ireland should not be eaten.
Dioxins were found in slaughtered Irish pigs, thought to have eaten contaminated feed.
Ms Gildernew said restrictions were put in place on Friday night when the situation began to unfold.
