The European Union will take a measured response to any further unilateral moves by the UK to delay implementation of the Northern Ireland Protocol, with senior officials signalling a staggered approach to legal action and arbitration, RTÉ News understands.

This would be to avoid falling into what diplomats fear would be the "trap" of escalating tensions around the protocol as the loyalist marching season in Northern Ireland approaches its peak.

The UK is widely expected to unilaterally extend a grace period which delays the ban on chilled meats entering Northern Ireland from GB, agreed with the EU in December, and which expires on 1 July.

However, it is understood the EU’s main interlocutor on the protocol, European Commission vice-president Maroš Šefcovic, has advised member states that the EU should avoid immediately responding with hard-hitting legal action, or even to retaliate by introducing tariffs or other measures through the dispute settlement mechanisms of the recently ratified EU-UK free trade deal.

Despite that, member states, especially France and Germany, have urged the European Commission to develop a range of "precise" legal responses to further unilateral moves by London.

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It is understood Mr Šefcovic has told member states the commission is considering three measures, which could be staggered over time.

The EU has already initiated infringement proceedings against the UK for unilaterally extending grace periods on food safety and animal health measures without consulting the European Commission.

In March, the commission issued a "letter of formal notice", the first step in legal action under the Withdrawal Agreement.

The EU has largely rejected the UK’s response to the letter, and the next step - a "reasoned opinion" - could be issued shortly.

It is understood that Mr Šefcovic has told member states that that legal track could end up in the European Court of Justice as early as September.

The second approach would be to initiate arbitration proceedings through the Withdrawal Agreement, and a third would be to trigger retaliatory measures through the Trade and Cooperation Agreement (TCA), which covers the future relationship between the EU and UK.

It is understood the EU regards this third option as the most serious. Diplomats suggest the EU will not immediately trigger that option if the UK unilaterally extends the grace period for chilled meats, including sausages, on 1 July.

Instead, the commission is recommending that such action would be as a result of cumulative unilateral action by the UK, and a failure to implement the protocol, over time.

"The British press seem to be developing the narrative that if they unilaterally extend the grace period at the end of the month then the EU will automatically react," said one source, familiar with a briefing Mr Šefcovic gave to EU ambassadors.

"The EU doesn't want to get sucked into the stupid sausage war type narrative, where we would be seen to be coming heavy because of things like chilled meat, sausages etc."

Meanwhile, it is understood the EU will accelerate a solution to the medicines issue, which has provoked headlines in recent weeks.

Mr Šefcovic is understood to have told member states that the EU should not be accused of holding up the supply of medicines from GB to Northern Ireland as a result of technical aspects to the protocol.

Officials are thought to be exploring options whereby any medicines produced in GB can be licensed to be sold in Northern Ireland, despite the fact that the protocol originally envisaged the European Medicines Agency being primarily responsible for authorising drugs, and "authorised holders" of licences needing to be located in Northern Ireland or in an EU member state.

The commission has also told member states that the protocol does not alter the fact that the UK is primarily responsible for public health in, and the supply of medicines to, Northern Ireland.

Despite the deepening tension between both sides, EU sources say they hope that the technical talks between the EU and UK on the Protocol could deliver a breakthrough at some point.