The Moriarty tribunal could be over in a matter of months, Taoiseach Bertie Ahern told the Dáil.
He said he understood it was Mr Justice Moriarty's intention to finish as quickly as he possibly could, subject to the procedures he was required to follow in his final report.
"I understand Mr Justice Moriarty and his staff are anxious to finish their work in a matter of months."
Replying to Opposition questions, Mr Ahern said the tribunal had cost his department €29.7 million since it was established in 1997.
The total payment made to the legal team was €23.1 million.
Fine Gael leader Enda Kenny said he had noted that a prominent businessman was seeking to restrict the tribunal chairman in the types of conclusions he could make in his impending report.
"The outcome of that challenge will affect the reports of all tribunals, including the Mahon tribunal, which is inquiring into other matters relevant to the Taoiseach."
Mr Ahern said there had been several cases in the past decade relating to tribunals, "and it is irrelevant whether I have a view".
Mr Kenny asked when the Moriarty tribunal's report on payments to Independent TD Michael Lowry would be completed.
Mr Ahern said he was not privy to the tribunal's day-to-day arrangements, but he understood that it should be able to begin preparation of its report in a matter of weeks.
While it was not possible to indicate when the second part of the report would be finalised, his officials had told him it was hoped that this could be done within a matter of months.
Caoimhghín Ó Caoláin, Sinn Féin's Dáil leader, said that some people under investigation by the Moriarty tribunal were major tax-avoiders who continued to avoid paying their fair contribution to the exchequer through loopholes in the tax system.