Fine Gael is to lodge a formal ethics complaint over the appearance of Minister of State for Finance Tom Parlon in a newspaper advertisement endorsing a brand of cattle feed.
Fine Gael Westmeath TD Paul McGrath accused Mr Parlon of demeaning his public office by appearing in an advertisement holding a bag of calf feed.
He said he was making a complaint to the Standards in Public Office Commission, which investigates alleged breaches of ethics guidelines for TDs and Ministers.
Yesterday Mr Parlon rejected accusations of a breach of ministerial conduct, and said he had received no payment for appearing in the advertisement.
A spokeswoman for the Progressive Democrats said the product in question was made by a neighbour and friend, and that Mr Parlon used it on his farm at Coolderry, Co Offaly.
"He uses the product himself, and he received no payment for it. He was doing this in his capacity as a farmer and he believes the product is good.
"While he does not want to prejudge the outcome of any complaint, he rejects any suggestion he breached ethical guidelines."
The advertisement for Grennan & Sons animal feed in last week's Irish Independent's farming supplement featured testimonials from three farmers, including Mr Parlon.
He is quoted directly about one product he used for weanlings, saying that animals on the feed had enjoyed good weight gain and sold for strong prices.
Mr McGrath, however, described Mr Parlon's appearance in the advertisement as "demeaning of his office".
"It think it's outrageous; I've never seen anything like it in all my years in politics." The appearance of Mr Parlon was inappropriate, he added. "Where will it stop? If Tom Parlon can do this, does this mean any Minister can do it? It leaves it open in my view to bring [ politics] into disrepute, and in my view it should not be allowed."
The standards commission's code of conduct gives no direct guidance on the appearance of Ministers in advertisements. It stipulates that office-holders should not be involved in any professional practice, should not be a director of a company or take part in any decision-making regarding a private company.
It does advise that office- holders "should not engage in any activities that could reasonably be regarded as interfering or being incompatible with the full and proper discharge by them of the duties of their office".