The Taoiseach may have to declare discounts or gifts given to his daughter for her wedding under guidelines issued by his own office.
The cabinet handbook's section on ethics legislation advises that office-holders, including the Taoiseach, are required to declare gifts, discounts or income received by spouses or children, if there is any possibility of a potential conflict of interest.
Under ethics legislation, all Oireachtas members are required to make an annual declaration of registerable interests, including gifts, shares and land, which is published annually.
However, cabinet members are subject to even stricter guidelines pertaining to their families' interests.
The cabinet handbook states that office-holders are required to make "an additional statement of the registerable interests of which office-holders are aware, of their spouses and of any children, which might reasonably be seen as capable of influencing them in the performance of their office".
This includes gifts or discounts worth €635 or over, from entities which could benefit directly in the future from the decisions or actions of the Taoiseach acting in his official capacity. Gifts from personal friends and family are excluded.
This additional statement is made to the clerk of the Dáil, but is not published.
Therefore the Taoiseach could be obliged to provide information on any gifts or discounts his daughter, Georgina, received from Irish firms who could benefit from Government decisions or State grants.
The Taoiseach is also facing calls to clarify what restrictions, if any, he faced in terms of speaking to the media because of an exclusivity deal between his daughter, son-in-law and Hello! magazine.
Under the deal the couple were prohibited from speaking to the media in advance of the wedding, or being photographed.
Other figures in the bridal party were also prohibited from speaking about the wedding.
Throughout last week the Taoiseach was unavailable to speak to the media about his daughter's forthcoming nuptials, while wedding organisers refused to say whether Mr Ahern was a party to the contract with Hello!.
A Green Party TD, Mr Dan Boyle,called on the Taoiseach to clarify what, if any contract he was party to, and whether that related to the office of Taoiseach.
"What the Aherns do in private is their own business, and if it's a private contract with the Ahern family, it's not an issue," he said. "But if it impinges on the office of Taoiseach it's a different matter, and that's what we have ethics legislation for."
"We're not totally adverse to the free market, but in terms of public image, it doesn't send out a very good one in advance of our presidency of the European Union if the Taoiseach is seen to be arriving protected by private security guards."