While I respect that the referendum on 23 June is one to be decided by the UK electorate alone, many Irish citizens living and working in Britain form part of that electorate. Ireland is also the UK’s nearest neighbour and our relationship with Britain is closer than with any other EU member state.

Ireland has a unique perspective on the outcome of the referendum, given the close and multi-layered nature of our relationship with the UK. These ties find their political expression in the relationship between the two governments, and between the Irish government and the Northern Ireland executive, including through the north/south ministerial council and the British-Irish council. Crucially, for more than 40 years they have also been expressed through our common membership of the European Union.

There are four main reasons why we want Britain to remain in the EU. There’s the economy – we want to sustain our mutual economic growth. We trade around €1.2bn (£900m) of goods and services each week between our two countries. Anything that gets in the way of that flow of trade will add costs and be damaging. There are 200,000 jobs in Ireland and another 200,000 jobs in the UK that are directly supported by our trade. More people work in the UK for Irish food companies than work for Nissan in Sunderland. World-leading Irish employers such as Greencore, Kerry, Glanbia and ABP all employ more local UK workers today because they have the EU rights of free movement of labour, raw materials and their finished products, without the costs of tariffs or barriers.

A decision to leave would mean the EU’s western boundary would go from Derry to Dundalk

There’s the EU itself. The EU needs renewal and we need a strong UK at the table to help to drive the reform agenda that can help the union regain competitiveness and growth. The UK and Ireland are like-minded on EU matters, and the process of working together in Brussels has built an immense store of knowledge, personal relationships and trust between our governments. The prospect of this resource being diminished by the absence of the UK in Brussels is not welcomed by me or my government.

There is the relationship between Britain and Ireland. Preserving that strong relationship would be more challenging if the UK left the EU, including with regard to the common travel area, which allows for the passport-free movement of people between these islands.

And there’s Northern Ireland. Our common membership of the EU provided an important backdrop to the Irish and UK governments working together to secure peace in Northern Ireland. The peace process was built by the people of this island coming together, and that will of course continue. When the Good Friday agreement was concluded 18 years ago, the detail of the negotiations and the agreement itself were brought about as a result of intensive engagement by the British and Irish governments in conjunction with the Northern Irish political parties. But often underestimated was the international support for the process, not least that of the European Union. The EU directly provides, and will continue to provide, much-needed funding to Northern Ireland – almost €3bn in the six years to 2020, helping the Northern Irish economy and supporting new sustainable jobs.

We share the UK’s only land border with another EU member state. Those many thousands of UK visitors to Ireland in recent years know that the border between both parts of Ireland is barely visible. There is a seamless flow of people crossing that border.

If the UK’s decision is to leave the EU, this will no longer be a border between two countries. It will be a border between the UK and the remaining 27 member states of the EU. It will be the EU’s western boundary running from Derry to Dundalk.

New administrative arrangements could be worked out, but there is no possible version of such a development that would avoid extra costs to governments, to business, to consumers and to the convenience of tourists and citizens travelling between our two countries.

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What is not easy to quantify and mitigate is the psychological effect of a hardening border on the island. My fear is that it would play into an old narrative – one of division, isolation and difference.

Our two governments and the great majority of people across these islands have worked in partnership to promote peace and reconciliation in Northern Ireland. In the process, British-Irish relations have been transformed. This was marked by the historic visit of Queen Elizabeth to Ireland in 2011 and the reciprocal first ever state visit to the UK by our head of state, President Michael D Higgins in 2014.

The re-establishment of a hard border on the island of Ireland would be a step backwards and present an opportunity for others, with malign agendas, to exploit for destructive purposes.

In stating the Irish government’s position, we do so as a close neighbour of the UK, a European partner and a co-guarantor of peace in Northern Ireland. And as a friend. Our common membership of the EU provided an important external context to the Irish and UK governments working together for peace. It should not be discounted lightly.

Voters have many issues to weigh up and the Irish perspective may not be foremost in their calculations. I hope, however, that some consideration will be given to that perspective, and that everyone who has an interest in Ireland will reflect on how best to use their vote.