The European Commission has rejected a UK compromise proposal on the Northern Ireland Protocol that would require the EU to take a more flexible approach to the issue of food safety and animal health, RTÉ News understands.
The British government has been pressing the EU to adopt a risk-assessment approach to managing large volumes of food of animal origin entering Northern Ireland from Great Britain, under the terms of the Protocol.
However, it is understood that, following an exploration of the issue within the European Commission, it has been concluded that allowing more flexibility based on risk would jeopardise the EU's body of rules on food safety and animal health, and run counter to the EU's zero-risk approach.
In response, the EU is reviving the idea that the UK align with EU food safety rules, possibly on a temporary basis, as the most decisive way of dealing with the burden of checks and controls on the Irish Sea.
Under the protocol, Northern Ireland remains within the EU's single market for goods, meaning it will continue to apply EU food safety rules and apply those rules to food products entering from Great Britain, which has become a third country.
This means that large consignments of food being supplied to Northern Ireland supermarkets will require cumbersome export health certificates, and will need to be signed off by a vet, if those products contain meat, eggs or dairy ingredients.
The protocol also means that chilled meats, including sausages, mince, pies and un-frozen prepared meals containing meat, would be prohibited from entering Northern Ireland from GB.
The latter prohibition was waived for six months thanks to an agreement reached between Brussels and London in December.
The need for export health certificates was waived for three months until 1 April, but the UK government extended that grace period unilaterally. The European Commission has issued legal action because of that move.
Despite that, EU and UK officials are said to be in daily contact on the protocol. It is understood that both sides are working towards a joint document, or roadmap, on the way forward, and that a meeting of the Joint Committee, which is the high-level political forum for managing the protocol, could meet by the end of May.
"The idea is that there wouldn't be a Joint Committee meeting unless there was something to agree," a diplomat told RTÉ News.
"They wouldn't hold one just for the sake of holding one. This road map/work programme is going through various evolutions as they try and converge on a document that both sides can agree on. It's possible that something may be ready by the end of May."
However, it seems certain that the food safety element of the discussions will not be resolved by the end of May.
Officials are said to be close to reaching agreement on how to manage the movement of pets from GB to Northern Ireland, as well as the question of tariffs on steel imports into the North.
The UK has been pressing the EU to take a targetted, risk-based approach to the issue of food consignments entering Northern Ireland, to determine the precise risk to the single market or consumer health of a particular product.
It is understood that the food safety and health directorate of the Commission, DG SANTE, has held a detailed, internal debate on the issue, along with the Commission's legal services.
However, while the risk-based approach has been included within the protocol when it comes to customs, the Commission has concluded that a risk-assessment approach is not compatible with EU legislation, and the precautionary principle.
"There was quite a lot of work done on the idea of risk," said the diplomat, "the idea that [sanitary and phytosanitary (SPS)] controls could be looked at on a risk-based approach, as in, what is the real risk to the integrity of the [EU] single market if a sausage migrates from Scotland to Belfast."
The diplomat added: "The Commission did internally look at this in some depth, but when you get into SPS you have the precautionary principle which is based on zero-risk, or something close to zero-risk. Then it becomes very difficult to be consistent with the precautionary principle. They concluded that a risk-based approach won't work in terms of the EU’s legislative regime."
As a result the European Commission is pressing the UK to think again about a separate veterinary agreement as the best way to deal with the food issue comprehensively.
Officials have been suggesting that such an agreement - based on the UK aligning with EU food safety rules - did not need to be permanent, and could be revisited if the UK concludes a free trade agreement with the United States.
This is because, based on historical US demands on agricultural products, a UK-US trade deal might not be compatible with EU food safety rules.
"[An EU-UK veterinary agreement] could be adjusted if the UK subsequently signs an agreement with the US which requires them to change their [food safety] regime in a way which is not compatible with the EU regime. Then you could come back to the situation and see what could be done," the diplomat said.
The UK has long rejected an EU-UK veterinary agreement based on alignment, preferring a so-called "equivalence" regime, such as that currently in operation between the EU and New Zealand.
However, EU officials counter that the volume of trade with New Zealand is vastly smaller than that between GB and Northern Ireland, and that an equivalence regime will not eliminate the need for checks and controls on the Irish Sea, but will only reduce the need.
Despite the apparent deadlock on the food issue, diplomats believe that a compromise could be found, although it would take some time.
"There is a continuing hope that some path forward may be found along those lines," said a diplomat. "You can use different words than alignment, it could be something else. The label might be different from the label normally used, but the end result might be the same."
Meanwhile, the UK's David Frost and his EU opposite number Maroš Šefčovič are expected to meet more stakeholders and businesses in Northern Ireland on managing the protocol, possibly as early as next week.
If there is a Joint Committee meeting on the Protocol at the end of May, co-chaired by Mr Frost and Mr
Šefčovič, it could coincide with the first meeting of the Joint Partnership Council, which governs how the future relationship treaty is managed.