Leo Varadkar (Dublin West, Fine Gael) | Oireachtas source

It would also mean new barriers to trade between Northern Ireland and the rest of the UK, and all the political problems that would arise from that, particularly for the unionist community.

We are working towards a new relationship between the United Kingdom and the European Union that allows free trade and free movement of people to continue between all parts of Britain and all parts of Ireland, if that is possible. If that is not possible, we have that guarantee around what I call the backstop and what Prime Minister May calls the last resort, which is a unique arrangement for Northern Ireland. That should not be our preferred solution. Our preferred solution should be ongoing free trade and free movement of people between Britain and Ireland, which is so important not only for citizens in Northern Ireland but also for Irish industry and Irish jobs.

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