The IDA has stepped “far outside its proper remit” in calling for a Yes vote in the forthcoming referendum on marriage, Christian group Iona Institute has said.
Chief executive of the investment body IDA, Martin Shanahan, told The Irish Times in an interview a Yes vote would be in the State's economic interest.
He also said a No vote against same-sex marriage would send a very negative signal to the world of international business.
Responding on Friday, director of the Iona Institute David Quinn said the call was "completely unacceptable".
“By intervening in the referendum in this way, the IDA is stepping far outside its proper remit. It is simply risible for it to pretend that its brief to improve Ireland’s economic prospects gives it permission to do this.
“On this basis, why not say what government we should vote for next time? Who we have in Government is much more relevant for the economy and for our multi-nationals than our definition of marriage.”
Mr Quinn said many major economies did not have same-sex marriage and there was “no evidence that this affects them in any way”.
“The intervention by the IDA in this debate is simply one more example of a major institution of ‘Official Ireland’ breaking its normal stance of neutrality in these matters to strong-arm Irish people into voting No.
“If we vote No it will not affect the Irish economy in any way, shape or form.”
Companies supported by the IDA employ more than 174,000 people in Ireland.
Mr Shanahan said in the interview that many of its clients were on record on this matter here and in the US.
“Overwhelmingly I think large multinationals in the US have come out in favour of same-sex marriage,” he said.