The French ambassador to Ireland Stéphane Crouzat has said European Union discussions would be needed on taxing multinational companies here, if other talks fail.
It comes as a verdict on the initial appeal of the ruling that US tech giant Apple owes €13bn in back taxes to Ireland is due on Wednesday.
In 2016, it was ruled by the European Commission that the Irish State must recover tax benefits given to the firm.
However it is expected that no matter the verdict on Wednesday, the case will be appealed again by the losing side.
Ambassador Crouzat told The Hard Shoulder: "We're not saying to harmonize the tax rate, what we're saying is there needs to be a level playing field in the way, an equality of treatment throughout the different countries in the way big, digital companies are taxed.
"Money made by a digital company in a country should be reverted in the form of tax to the country where the money was generated.
"So it's not a question of harmonizing everything, including the tax rate, it's a question of having fair play.
"That's why we were very keen to, and still are, to have a very profound discussion to try and harmonize this.
"And Ireland, in fact, is being open about it and recognises the fact that we need to have fair taxation on digital companies.
"You, the Irish, prefer to do it within the OECD - which is fine, we're very happy with that.
"But if we can't come up with a conclusion at the OCED, I think we'll want to revert to - well, we have a national tax that we are going to implement.
"And we would want to revert to EU discussions to try and go forward on that issue".
"Taxation is very important for the way the single market operates - so of course we are very much aware that it is a unanimous decision, and so we're not going to force anything on anybody.
"But I think everybody realises that in order for the EU to function as best it can, the rules of the game have to be fair".