The majority of political parties in Northern Ireland opposed the UK leaving the EU .
The DUP having supported the UK leaving the EU , while nationalist parties and most others opposed , fearing among other things the possibility of a hard border resulting with the Republic of Ireland.  , BBC2 , 1 March 2017 It became known during the campaign that the DUP spent £282,000 on a pro-Brexit advert in a newspaper that does not come out in Northern Ireland .
2017 Northern Ireland Assembly election