Former president Mary McAleese has described Brexit as like pulling a tooth with 10,000 roots.
She has also spoken of her worries about what the implications might be for Ireland.
In an interview with RTÉ News, she said that given the importance the British government attaches to controlling immigration and leaving the European Union's Customs Union, she fears that the return of border controls including identity checks along the border is inevitable.
She said she would be heartbroken and deeply, deeply unhappy if she was required to produce some form of identity each time she crossed the border.
In relation to the papers and other information provided by the British government so far, she said "we need to start hearing how it will be alright".
We need your consent to load this Facebook contentWe use Facebook to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences
In relation to the current situation in Northern Ireland and how it is being affected by Brexit, she said she is worried about the future of power-sharing.
She said that the prospect of a united Ireland is one of the issues that has emerged as a result of the Brexit situation.
She stressed the need for new language, new ideas and new understandings to take account of the unionist population.
Mrs McAleese was interviewed by RTÉ News in Edinburgh, where this afternoon she was the guest in a show hosted by former Scottish National Party leader Alex Salmond, as part of the Edinburgh fringe festival.
