"This is all the more disappointing because it undermines the critically important arrangements for joint management of mackerel by the Coastal States under the UN structure.
"As the scientific advice sets the sustainable level of fishing each year on mackerel, an increase by Norway means either the stock is overfished or other parties must take a smaller share.

"Neither option is acceptable.”

Before Britain's departure from the EU, mackerel was managed under a UN Coastal States Agreement, which included the EU, Norway and the Faroe Islands.

However, this year, the new parties have not been able to put a new Coastal States Agreement on the fish in place, following the UK's departure from the bloc.