A new row has broken out about post-Brexit trade arrangements with the European Union, centring on goods heading from Great Britain to Northern Ireland.
Since Britain left the single market at the end of December, there has been a grace period of minimal regulation on certain goods arriving in Northern Irish ports.
It was to stop supermarkets there running out of supplies and was itself due to run out at the end of the month.
Businesses in Northern Ireland have been pressing for an extension to the grace periods to avoid a cliff-edge plunge into extra bureaucracy linked to the post-Brexit Northern Ireland Protocol.
Should the grace period have finished at the end of this month then supermarkets would have had to produce export health certificates for all shipments of animal products, since Northern Ireland is part of the EU’s single market.
However, the UK government extended this grace period until October, without any consultation, something the EU claims is breaking international law.
Westminster has defended its decision as the minimum step necessary.
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Newly appointed Cabinet member Lord David Frost said the UK’s intervention should allow time for constructive discussions with counterparts in Brussels.
A UK Government spokesperson said: “Lord Frost explained that the measures announced today, following official-level notification to the Commission earlier this week, were temporary technical steps, which largely continued measures already in place, to provide more time for businesses such as supermarkets and parcel operators to adapt to and implement the new requirements in the Protocol.”
The former Brexit negotiator in charge of forging the UK’s new relationship with the bloc spoke to Commission vice-president Maros Sefcovic on Wednesday.
Mr Sefcovic has said the UK is in violation of its post-Brexit obligations.
The UK Government added: “He [Lord Frost] underlined that these were needed for operational reasons and were the minimum necessary steps to allow time for constructive discussions in the Joint Committee to continue without the prospect of disruption to the everyday life of people in Northern Ireland in the coming weeks.”
The spokesperson added that such operational measures were “well precedented” in other international trade arrangements.
Britain is set to breach international law for a second time, vice-president Sefcovic has warned.
The Irish government also branded the intervention extending the soft-touch regulatory regime on some goods entering Northern Ireland from Great Britain as “deeply unhelpful”.
A commission statement on behalf of Mr Sefcovic said: “Following the UK government’s statement today, vice-president Sefcovic has expressed the EU’s strong concerns over the UK’s unilateral action, as this amounts to a violation of the relevant substantive provisions of the protocol on Ireland/Northern Ireland and the good faith obligation under the Withdrawal Agreement.
“This is the second time that the UK Government is set to breach international law.
“This also constitutes a clear departure from the constructive approach that has prevailed up until now, thereby undermining both the work of the Joint Committee and the mutual trust necessary for solution-oriented co-operation.”
The protocol is designed to prevent the imposition of a hard border on the island of Ireland by keeping Northern Ireland following EU trade rules.
It has caused disruption to some goods travelling from the rest of the UK after suppliers encountered extra red tape.
Northern Ireland Secretary Brandon Lewis said: “As part of the pragmatic and proportionate implementation of the Northern Ireland Protocol, the government is taking several temporary operational steps to avoid disruptive cliff edges as engagement with the EU continues through the Joint Committee.
“These recognise that appropriate time must be provided for businesses to implement new requirements, and support the effective flow of goods between Great Britain and Northern Ireland.”
Ministers face a backlash from unionists who fear the protocol threatens Northern Ireland’s place in the UK internal market.
Mr Lewis said: “For supermarkets and their suppliers, as part of the operational plan the UK committed to at the UK-EU Joint Committee on February 24, the current Scheme for Temporary Agri-food Movements to Northern Ireland (STAMNI) will continue until October 1.
“Certification requirements will then be introduced in phases alongside the rollout of the Digital Assistance Scheme.”
He said further guidance will be provided later this week on parcel movements from Great Britain to Northern Ireland, to provide necessary additional time for traders beyond April 1.
Guidance will also be set out to help address practical problems on soil attached to the movement of plants, seeds, bulbs, vegetables and agricultural machinery.
Irish Foreign Affairs Minister Simon Coveney said: “A unilateral announcement is deeply unhelpful to building the relationship of trust and partnership that is central to the implementation of the protocol.”