Brexit: Northern Ireland driven 'back into silos'
Twenty years ago the historic Good Friday Agreement was signed in Northern Ireland which put an end to three decades of sectarian conflict.
But now, Monica McWilliams, one of the few women who was at the negotiation table, says the Brexit vote has created uncertainty.
"We cannot go back to a border between the north and south," she told BBC Hardtalk's Stephen Sackur.
Nobody really thought about the impact Brexit would have on Northern Ireland when they went to the polls in June 2016, she said.
Watch the full interview on Thursday 5 April 2018 on BBC World News and Friday 6 April on the BBC News Channel, or watch again on BBC iPlayer (UK only)