The German Chancellor Angela Merkel has said a solution must be found to avoid a hard border in Ireland, in the event of a no-deal Brexit.
Speaking in Dublin, Ms Merkel said: “We will simply have to be able to do this…where there’s a will there’s a way. We still hope for an orderly Brexit.”
But the UK is currently scheduled to leave the European Union (EU) on 12 April unless a further extension to the Brexit negotiating process, known as Article 50, is granted.
That has put a fresh focus on what could happen to the Irish border, if there’s no deal.
The UK and Irish governments and the EU have been consistent that, whatever happens, there will be no hardening (ie physical checks) at the border.
But keeping that promise could be challenging.
What’s the problem?
If the UK leaves without a deal, it will cease to have a trade deal with the EU.
The EU imposes a range of checks at its borders for countries like this.
There are customs checks, like those on the Norway-Sweden border, and product standard checks.
The checks on food products are strict – they must take place at border inspection posts located “in the immediate vicinity of the point of entry” into the EU.
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The EU says these border checks are necessary to protect what it refers to as the “integrity” of its single market and customs union.
Essentially, it means that the EU wants to prevent products entering its market that could be unsafe or represent unfair competition.
The EU’s chief negotiator Michel Barnier has repeatedly emphasised that protecting the single market is a key objective for the EU.
What has the EU said?
The EU has made it increasingly clear that there would have to be some form of checks on cross-border trade in Ireland – but the question is how and where would they take place?
“We have to implement everywhere, at each and every external border of the EU, three types of controls” to protect consumers, businesses and national budgets, says Mr Barnier.
“We need to find the way somewhere to implement the checks. We’re working with the Irish government to know where we can apply these checks.”
What checks could happen away from the border?
The Revenue Commissioners, Ireland’s tax authority, has suggested that while all customs declarations could be filed electronically, up to 8% of consignments would still need to be physically checked for customs purposes.
It says it is exploring ways of doing this at traders’ premises or at designated warehouses.
Brexit supporters and some government ministers have seized on suggestions like this to say that there is no real problem.
“Solutions have been come up with that don’t involve a hard border, that involve doing checks elsewhere,” Liz Truss, the chief secretary to the Treasury, told the BBC.