The twelve nautical mile limit pertains to fisheries and it gives exclusive rights to United Kingdom registered fishing vessels to fish in those waters. Between six and twelve miles some fishing vessels, flying the flags of other nations, have historical fishing rights.

The twelve nautical mile limit pertains to fisheries and it gives exclusive rights to Irish registered fishing vessels to fish in those waters. Between six and twelve miles some fishing vessels, flying the flags of the U.K., France, Belgium, The Netherlands and Germany, have historical fishing rights.