DUBLIN (Reuters) - Ireland will not impose any restrictions along its now open border with British-run Northern Ireland if Britain quits the EU without a deal but will need to take “some action somewhere” to protect the EU single market, its foreign minister said.

FILE PHOTO: Protest signs left by anti-Brexit campaigners, Borders Against Brexit are left outside Irish Government buildings in Dublin, Ireland April 25, 2017. REUTERS/Clodagh Kilcoyne/File Photo

The Irish government meanwhile released an update to its Brexit contingency plans stating there were no easy answers on how to avoid the need for physical infrastructure on the island of Ireland in case of a disorderly British exit from the EU.

How to manage the land border between EU-member Ireland and Northern Ireland - including an emergency “backstop” solution to prevent the return of extensive controls - remains the most contentious part of Britain’s divorce deal the contenders to become the next British prime minister want renegotiated.

“The truth is we will need to take some action somewhere in our economy to ensure we are protecting the integrity of the products that are going to be sold on out of Ireland,” Foreign Minister Simon Coveney said on Tuesday, referring to cross-border checks, especially animal products, in a no-deal Brexit.

“(But) we are not going to put checks on the border or close to it,” he told reporters in Dublin.

In a no-deal scenario, Ireland has pledged to impose the necessary checks to preserve its full participation in the EU single market while avoiding any related infrastructure - a task Coveney said has not been easy to resolve in contingency talks with Brussels that began early this year.

Both sides had made progress, he added, but were not where they needed to be ahead of the current Oct. 31 Brexit deadline.

In its updated plans, the government said North-South trade could no longer be as frictionless as it is today in a no-deal Brexit and that any arrangement to minimise the negative consequences would clearly be sub-optimal.

That is why retaining the backstop is “an absolute red line” for Ireland, Prime Minister Leo Varadkar said on Monday.

“FAR REACHING CHANGE”

A no-deal Brexit also risks significantly undermining wider community relations and political stability in Northern Ireland, with potential related security concerns, the document said.

It pointed to public statements from the police that any border infrastructure or personnel would become targets for sectarian militants.

The 500-km (310-mile) frontier was marked by military checkpoints until a 1998 peace deal ended three decades of violence between Catholic nationalists seeking a united Ireland and Protestant unionists who wanted to keep Northern Ireland British. More than 3,600 people were killed in that conflict.

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Additional Irish police resources have been deployed to border areas in recent months, part of a general increase in recruitment, the updated plan said. It said that further resources could, and would, be redeployed immediately in the event of a no-deal Brexit.

The 117-page document, which built on one of the largest-ever pieces of legislation lawmakers passed in March to prepare as best as possible for a no deal, described the impact of such an outcome on Ireland as “profound on all levels.”

With close trade links and a shared land border with Britain, Ireland is considered the most vulnerable among remaining EU members to Brexit. The government has already warned that the fast growing Irish economy could suddenly contract if Britain crashes out, shutting down businesses and putting up to 80,000 jobs at risk.

Significant short-term risks identified on Tuesday included delays at ports that would disrupt trade not just to and from Britain, but via the British “landbridge” that some 60% of Irish exporters use to move goods to mainland Europe.

It also stated that goods such as live animals and animal products that require checks and come from the United Kingdom, of which Northern Ireland is a member, will be subject to a minimum 24-hour notification period.

Such an imposition of regulatory requirements and tariffs would contribute to far-reaching change on the island of Ireland, the document said, particularly so for North-South trade.

“Make no mistake, a no-deal Brexit will be an ugly prospect. There is no sugar coating of that message,” Coveney said.