Peter Mandelson has said Northern Ireland's economic prosperity will be severely set back if the UK votes to leave the European Union.
The former Northern Ireland Secretary of State and European Commissioner for Trade was addressing business people at an Manufacturing NI event at the Belfast Harbour Commissioner Office on Friday ahead of the EU membership vote on June 23rd
Lord Mandelson told delegates the EU brings huge economic privileges and opportunities and there can be no half measures in the event of Brexit.
“If we take ourselves out of the European Union we wil be taking ourselves out of the single market as well,” he said. “There is no half measures. There is no, I’m afraid, possibility of being, as it were, half pregnant.
“You are either in the club, accepting the rules, making a financial contribution or you are out.”
Lord Mandelson claimed Brexit would make it “harder to do business” as trading terms would change and anyone telling people the UK would continue to enjoy the same privileges “are trying to take you for a ride”.
He was joined at the panel event by Conservative MEP Daniel Hannon, DUP and Sinn Féin MEPs Diane Dodds and Martina Anderson and others.
Mr Hannon invited voters to put him out of a job by voting to leave and described the EU as a “hangover from the 1970s”.
He said: “Countries prosper when decisions are made as closely as possible to the people that they affect.”
Agricultural economist Dr Thia Hennessy, head of Agricultural and Farm Surveys at Teagasc, said farmers in the North are concerned because CAP makes up 87 per cent of income. "There is no guarantee Westminster would continue to support farmers by the same magnitude if there was a Brexit," she said.
Dr Hennessy also said farmers in the Republic she deals with “are very much hoping for remain” but she is aware farmers in the North are split on the matter.
"About a third of the milk produced in Northern Ireland crosses the border to be processed. We can do that at the moment because we are one market. How much we could do that in a Brexit scenario is questionable," she said.
Earlier, Deputy First Minister Martin McGuinness launched Sinn Féin's remain campaign Put Ireland First at the Europa Hotel in Belfast.
"Ireland's place north and south is leading change in Europe, " he said.
Mr McGuinness said Brexit would have “huge implications for the island”. He said “the narrow interests of a section of the Tory party” should not take the North out of Europe and “set our political agenda”.
“Brexit would be bad for Ireland, bad for business and trade, bad for our farmers and bad for human rights and workers’ rights,” he added.