The decision by the people of Northern Ireland to remain within the European Union has highlighted the need for reunification, Sinn Féin MEP Liadh Ní Riada has said.
Ms Ní Riada told the annual Kilmichael Commemoration in west Cork on Sunday the Brexit vote in June clearly showed people in the north voted "very clearly" to remain.
“Having one part of Ireland in and one part out will spell disaster for the entire Ireland - it will effectively repartition the country. Partition was a bad idea in 1921 and to entrench it further after 95 years of abject failure is utter madness,” she said.
Ms Ní Riada said Northern Ireland exiting the European Union would be an enormous setback for the economy, and would affect trade in all of Ireland and internationally.
She said the repercussions of a physical border would spread far beyond the border counties.
“Partition has stunted the growth of this island’s economy for almost a century. We must make it clear to the British, Irish and European governments that we, the Irish people, reject borders, hard or soft, British or European, in our country,” she said.
“There are those who only pay lip service to reunification. They tell us that now is not the time but now is exactly the time as the current political landscape does not only present an opportunity for reunification, it demands it.”
“Unity is not in the gift of the British government - it now rests in the hands of the people, north and south, to be expressed in concurrent referendums. We need to secure a vote for the people and win the vote for unity.”
Sinn Féin has published a document entitled Towards a United Ireland, which will set out the case for unity.
Ms Ní Riada said reunification cannot be the responsibility of Sinn Féin alone and it was time for activists in other parties to play a role in the discussion that would shape the new Ireland.
“To our unionist brothers and sisters, I say your input is as essential as everyone else’s, take part in the conversation, even from an opposing point of view. Share with us your hopes, concerns, and ideas and we will share with you our vision of a fair, free and progressive country.”
Earlier, Ms Ní Riada delivered an oration at the General Tom Barry Commemoration in Fitzgerald Park in Cork city where she paid tribute to Tom Barry's wife, Leslie de Barra.
Ms de Barra carried messages and ammunition, and attended to the wounded while she was stationed in the GPO during Easter Week.
"A tireless humanitarian, she established the anti-hunger charity Gorta and went on to become the president of the Irish Red Cross, being awarded the Henry Dunant Medal in 1979, the highest honour of the global Red Cross Movement," Ms Ni Riada said.