What is Article 16 and what happens if UK triggers it?

The European Union is likely to take legal action if the UK triggers Article 16 of the Northern Ireland protocol, a set of post-Brexit rules in place to prevent a hard border between Northern Ireland and the Republic of Ireland.

It comes after the UK government issued a new warning to the EU that it will not shy away from triggering Article 16, with grace periods coming to a close.

A command paper published by the UK in July proposed radical changes to the protocol and set out the tests the UK would apply to trigger Article 16, a part of the Protocol which allows some parts of the deal to be set aside if they are severely impacting everyday life.

The NI protocol was agreed as part of the Brexit deal and is designed to protect the Good Friday Agreement by avoiding a hard border on the island of Ireland.

To allow goods to move freely between NI and the Republic of Ireland and avoid that hard border, NI remained in the EU’s single market for goods as well as Great Britain’s market.

This means goods don’t have to be checked as they cross the Irish border, but some checks and controls are required on goods entering Northern Ireland from the rest of the UK.

This has caused difficulties for some businesses and is opposed by unionist parties in Northern Ireland.

Article 16 is a technical term given to a Brexit clause that allows the UK and the EU to suspend any part of the agreement that causes “economic, societal or environmental difficulties that are liable to persist, or to diversion of trade”.

The UK’s Brexit Minister, David Frost said the July “command paper” sets out that the tests to use Article 16 are met.

He said: ”[The EU] would be making a significant mistake if they thought that we were not ready to use the Article 16 safeguards, if that were to be the only apparent way forward to deal with the situation in front of us.”

Last week, Mr Frost escalated the threats on Twitter, where he wrote: “The Protocol is clearly having a continued negative effect on everyday life & business in Northern Ireland.

“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.”

However, the European Commission does not believe the conditions to trigger the clause have been met, and would challenge any triggering of the article on legal grounds.

If the UK triggers Article 16, it is understood that the EU would retaliate with legal action.

RTE reported that European Commission is preparing a hierarchy of responses should London trigger the clause.

As part of a “two-track approach,” the EU is “looking at things like further infringement [legal] proceedings, arbitration mechanisms, and cross retaliation into the [EU UK] Trade and Cooperation Agreement,” an unnamed diplomat told RTE.

They added: “The commission will challenge the UK invocation of the article legally because the view would be they do not have the right to invoke it, that the conditions are not there to invoke it.”

Brussels and Dublin are also expected to push back against any notion that a suspension of the goods provisions of the protocol would mean the obligation to check and control products entering the single market shifting back to the Irish land border, RTE reported.