Co Cork builder Owen O'Callaghan has issued a strongly-worded statement against evidence given at the Mahon tribunal by developer Tom Gilmartin.
Mr O'Callaghan said he had intended to reserve the comments for the tribunal however, having heard "the butchery of reputations" including his own he decided to release the statement today.
"I have decided to issue this statement as a result of increasing levels of frustration and despair at what I am being subjected at the hands of Thomas Gilmartin who has, since 29 May this year, been engaged in a tormented marathon of lies and bitterness under the dubious protection of tribunal privilege and, more seriously, immunity from prosecution which was issued to him by the DPP" he said.
Mr O'Callaghan denied any wrongdoing or ever giving money to the Taoiseach, Mr Ahern.
The statement read: "Neither did Mr Ahern, at any time, directly or indirectly, receive any monies from me, from any of my companies or from anyone acting on my behalf in respect of any project in which our company was involved.
"The allegations about some monetary connection between me and the Taoiseach at any time are completely false and have been deliberately constructed to inflict as much damage as possible."
Mr O'Callaghan continued by saying that Mr Gilmartin was engaged in a "vicious attempt" to discredit all those associated with Quarryvale and has "maliciously extended" his list of targets to include the Taoiseach and a former Taoiseach who are "wholly unconnected with the project and its history".
And he added that the Mahon tribunal provides Mr Gilmartin "the ideal vehicle for his mission".
"It is deeply disturbing to me that in a modern civilized democracy, a forum can exist where an individual can peddle such monstrous and clearly obvious lies with impugnity and immunity," Mr O Callaghan said.