The announcement comes after a report by the Constitutional Convention back in April, which voted overwhelmingly in favour of holding a referendum on legalising same-sex marriage.
Mr Gilmore announced that the referendum will take place next year, reports GCN.
The National Lesbian and Gay Federation, welcomed the announcement, and issued a statement.
Olivia McEvoy, Chair of the NLGF, stated: “The NLGF has always asserted that the issue of marriage equality should not require a public vote as marriage is a fundamental human and civil right that should be open to all citizens of this country. However, as the government has affirmed the need for a referendum on this issue, we will firmly give our support to the campaign to secure a Yes vote on the day of the poll.”
The public polls on this issue have shown consistent and ever growing support for full marriage equality for same-sex couples.
“We take great heart from the overwhelming vote at the Constitutional Convention last April to positively affirm the right of LGBT couples to marry under our Constitution, a result consistent with numerous public opinion surveys on the issue,” she continued.