DUBLIN (Reuters) – There is more work to do to establish how Irish border arrangements will look after Brexit, Northern Ireland’s Democratic Unionist Party said on Friday, after Britain and the European Union agreed the outline of a deal.

“We believe there is still more work to be done to improve the paper. Specifically, more work is needed around the areas of cooperation where it would be necessary to have alignment of rules and standards,” the DUP said, adding that more needed to be done to establish how alignment could be effected without staying in the EU’s single market and customs union.

The DUP also said that its support for the final deal would depend on its contents, and that it had cautioned British Prime Minister Theresa May about its reservations.