The Taoiseach has told the Mahon tribunal he doesn't understand how its investigations moved from inquiring into alleged payments made to him by developer Owen O'Callaghan to investigating "everything from cradle to grave".
Mr Ahern took the stand for a second day at the Mahon tribunal shortly before 10.30am.
He told counsel for the tribunal Des O'Neill he did not understand how he "was moved onto the J2 list" of those whose affairs it was investigating.
Mr Ahern said that category put him in a "catch-all" category, where the tribunal could investigate "everything from cradle to grave".
Mr O'Neill said this was "not a correct summary" of events and that the tribunal's examination yesterday focused on "following a money trail" traced through the correspondence outlined yesterday.
Mr Ahern is facing questions from tribunal lawyers about four cash lodgements in 1994 and 1995 totalling more than £180,000, all of which were preceded by foreign exchange transactions.
Mr Ahern accepted that the tribunal wanted to ask him further questions on a number of lodgements it is investigating.
He also accepted that documentation he had previously provided to the tribunal had not identified the source of various amounts lodged to his accounts and to accounts in the name of Mr Ahern's former partner Celia Larkin in 1994 and 1995.
Taoiseach Bertie Ahern
Mr O'Neill said the sums under investigation were all "large sums in cash". He accepted that Mr Ahern had given a "narrative" account of the lodgements but said that this was "not the question" he was being asked.
On the sum of £50,000 which Mr Ahern said he saved over a period of time in the early 1990s, the Taoiseach said he believed it was "a small amount of money" for someone on a ministerial salary to have saved.
He said someone saving the maximum for an SSIA account in recent years would have saved about half that.
Mr Ahern says he bought the sum of £30,000 sterling in 1995 from that money he had saved to return it to businessman Michael Wall. However, the tribunal has not been able to find a record of the purchase of that amount by Mr Ahern.
Yesterday, Mr Ahern insisted he had "done nothing improper".
However, he accepted he had not supplied the tribunal with the comprehensive information it requested concerning cash lodgements that the tribunal was investigating over a two-and-a-half year period.
Mr Ahern said he had attempted at all times to supply the information being sought by the tribunal but accepted that it was "not happy with the comprehensive explanation that I thought I had given you".
In an unusual move, tribunal chairman Judge Alan Mahon allowed Mr Ahern to read out a personal statement as he took the stand yesterday.
The Taoiseach said he had been involved in politics for more than 30 years and was in the totally unfair position of having to defend his honesty and integrity as a result of unfounded allegations.
"I have done nothing improper. I have done no wrong and wronged no one."
He said false allegations against him and the leaking of tribunal documents were calculated to do him huge personal and political damage.
The Taoiseach said he totally and utterly rejected the allegations made by developer Tom Gilmartin that he got money from Cork-based businessman Owen O'Callaghan. "I did not accept a bribe. I did not do anything for Owen O'Callaghan," he said.
Mr O'Callaghan has also denied any such payment to Mr Ahern and has also denied ever telling developer Tom Gilmartin that he did.