Thread by @tconnellyRTE

NEW: The EU is likely to challenge on legal grounds any move by the UK to trigger Article 16 of the Northern Ireland Protocol, @rtenews understands.

2/ Furthermore, the EU could resort to raising tariffs on UK products in retaliation, which officials say is provided for under the EU-UK free trade agreement.

3/ Although the UK government has repeatedly threatened to trigger Article 16, saying the conditions have already been met, the European Commission does not believe that to be the case, and would challenge any triggering of the article on legal grounds.

4/ While details have not been shared with member states, it’s understood the European Commission is preparing a hierarchy of responses should London trigger Article 16.

5/ “The Commission is internally of the view that Article 16 could happen at any time, that it hasn't gone away, that it’s a very serious possibility,” says a diplomat familiar with preparations.

6/ It’s understood the European Commission is working on a twin-track approach, on the one hand bringing forward new proposals that would ease the implementation of the Protocol, while on the other hand preparing a response to any Article 16 move.

7/ “In the second track they're looking at things like further infringement [legal] proceedings, arbitration mechanisms, and cross retaliation into the [EU UK] Trade and Cooperation Agreement. There's a sort of a hierarchy that gets more and more serious,” the diplomat said.

8/ “The Commission will challenge the UK invocation of the article legally, because the view would be [the UK] do not have the right to invoke it, that the conditions are not there to invoke it.”

9/ The preparations come against the backdrop of simmering tensions between London and Brussels over the Protocol, and a contested version of events surrounding British prime minister Boris Johnson’s meeting with US president Joe Biden in Washington this week.

10/ Despite the tensions, diplomats say there has been a slight improvement in the mood, with a phone call last week between the European Commission vice president @MarosSefcovic and his UK counterpart @DavidGHFrost.

11/ A meeting of the EU UK Specialised Committee, which manages the technical aspects of the Protocol, is taking place in Brussels today.

On Twitter yesterday Lord Frost said: “The Protocol is clearly having a continued negative effect on everyday life & business in NI

12/ “The outstanding issues now need to be dealt with urgently. I and my team are in contact with the EU daily, but we need a full response to our July Command Paper soon.”

13/ The Command Paper has called for sweeping changes to the Protocol, which the EU regards as an unacceptable renegotiation. Officials say Mr Sefcovic will bring forward proposals on customs, agrifood checks, medicines and an enhanced role for Stormont after the Tory party conf

14/ It’s expected technical talks involving both sides will intensify in the coming weeks. However, there are tensions over how the EU’s proposals are presented, with the UK insisting London will not accept ideas on a take-it-or-leave-it basis.

15/ “The British are indicating that it's not just the substance of these proposals that is important,” says a diplomat. “It's also the way in which they emerge. Basically, the British are saying this won’t work unless these proposals have an element of shared ownership.”

16/ Sh the UK trigger Article 16, it’s understood there would be strong push back by Brussels against any notion that a suspension of the goods provisions of the Protocol wd mean the obligation to control products entering the single market shifting back to the Irish land border.

17/ While such a scenario was being looked at in 2019, when a no deal Brexit was a possibility, on this occasion the context is different, say sources.

18/ In 2019, there was no legal fallback in place. Now, say EU sources, there is the international and legally binding Withdrawal Agreement, of which the Protocol is part.