A vote for the United Kingdom for leave the European Union, would be bad for Britain and Ireland.
We would be worse off as a 'Brexit' could restrict trade between our two countries, and tensions in Northern Ireland could increase if the free movement of people, goods and services on the island of Ireland comes to an end.
There is understandably considerable confusion over what exactly the UK's trading relationship with the EU will be if we leave it. If we had full access to the single market, then we would have to pay in and accept all the rules, and free movement of people, as Norway does. The other option would be to strike a separate trade agreement, as Canada has, but it is not an attractive route to take given it took them seven years to reach a deal, which excludes financial services and certain agricultural products.
If the UK left the EU without negotiating an alternative trade arrangement, World Trade Organisation rules would require the EU to impose the same external tariffs on the UK that it applies to other non-members.
This would see levies applied to a range of UK goods, for instance there is a 10 per cent tariff on car imports and 36 per cent on dairy products. The EU would have no choice but to apply them.
People in London sometimes forget that although Britain could vote to leave the EU, we can not abolish it. We would not be able to come to a separate trade agreements with Ireland or any other individual member state, only with the EU as a whole. The consequences for the agricultural sector could be significant. The UK is Ireland's largest agricultural trading partner, and takes around 35 per cent of Ireland's food exports. The beef and dairy sectors in particular could be badly hit in the event of a Brexit.
There would then be the practical matter of trying to police the only land frontier between the UK and EU. If we were in different trading zones, there would have to be customs posts along the 300 odd miles of border. As Brexiteers want to impose greater restrictions on the movement of people from Europe into the UK, there would no doubt have to be full border checks as well.
One upside for Dublin, is that it could benefit from financial sector jobs being moved out of the City of London. Outside of the European Single Market, banks based in the UK would require an alternative headquarters in the EU, as Swiss banks currently do. The Irish Central Bank is absolutely right to be considering this as apotential opportunity for Dublin.
It seems strange that the UK should be considering marking the centenary of the Easter Rising, by borrowing a political idea from Eamon De Valera; 'external association', the concept of complete political separation from your neighbour. In this case it would be separation from the whole of Europe, not just between Britain and Ireland.
Sovereignty is about the power of parliaments to shape the future of their country in a way that best serves the people they represent. Our membership of the European Union is an agreement that the UK has entered into freely, because we believe it is of benefit to our country, just as we have agreed to share responsibilities in defence agreements through out membership of Nato. Our membership of the EU is also of great significance to the strength of relations between Ireland and the UK, something which is hugely important to our future peace and prosperity.
Damian Collins is the Conservative MP for Folkestone and Hythe