Mike O’Leary, of Beulah Print, Drogheda, said that a complaint has been made under the Equal Status Act and it is alleging sexual discrimination.

In March, the Christian-run company defended its decision not to print the invitations for Jonathon Brennan, aged 29, and his partner John Kierans, aged 35, from Drogheda.

At the time, Beulah said: “We are not against homosexuals. However, we do not support same-sex marriage, which printing wedding invitations would do.”

Mr Brennan and his partner plan to marry in August.

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Mr Brennan yesterday declined to confirm if the complaint had come from the couple and said they wanted “to put the issue to bed”. He did not want to make any other comment.

Mr O’Leary said: “We can confirm that a complaint has been received which is now in the hands of the Equality Tribunal.

“The tribunal normally invites both parties to mediation in an effort to resolve the complaint so we expect this to take place shortly.”

On its Facebook page, Beulah Print stated: “Beliefs are what we hold true in our hearts. Our business is part of what we do with our lives here on earth. The two are part of who we are. How we do business is determined by what we believe. They can not be divided anymore than our hearts can be removed and we continue to live.”

The Equality Tribunal did not confirm whether a complaint has been made but did say the “the Equal Status Acts specifically provide that an investigation into a claim of discrimination must be held in private”.

Earlier this year, the Equality Commission for Northern Ireland brought a case against Ashers Bakery in Belfast after the family-run bakery turned down the request for a cake with an image of Sesame Street puppets Bert and Ernie below the motto Support Gay Marriage. This week it was found guilty of discrimination.

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