Irish PM Bertie Ahern has apologised to the Irish people for "misjudgements" he made over accepting loans and event money while finance minister.
Bertie Ahern said his motives had been "distorted"
Mr Ahern has admitted receiving loans from friends in 1993-94 and accepting £8,000 ($15,100) after a UK speech.
"I now regret the choices I made during dark and difficult times," he said.
However, he strongly denied any ethical or legal wrongdoing, saying the cash he received had nothing to do with his official position.
Pressure had been building for Mr Ahern to admit that he was wrong to take the loans and speech money.
At the end of a 15-minute statement that was largely a strong defence of his legal and ethical position, he said he offered his apologies to the Irish people and the Irish parliament, the Dail.
He said if he had known his actions would have caused such controversy and his motives would have been so "distorted", then, "I would not have accepted a penny".
Mr Ahern said: "It was not illegal or impermissible to have done what I did. But I now regret the choices I made.
"The bewilderment caused to the public about recent revelations has been deeply upsetting for me and others near and dear to me. To them and to the Irish people, I offer my apologies."
But his apology failed to halt a string of attacks from opposition leaders, who labelled his actions inappropriate, unethical and wrong.
Green Party leader Trevor Sargent said: "You have lost moral authority... Do the decent thing and resign."
Enda Kenny, leader of Fine Gael, said: "This is supposed to be accountability day... This Taoiseach (prime minister) is still the great evader."
The government had resisted demands from the opposition for a full debate, allowing only a 15-minute statement from Mr Ahern and five-minute speeches from the five opposition leaders.
The Irish Times newspaper last month revealed Mr Ahern received loans worth 50,000 euros (£34,000) from businessmen friends.
Mr Ahern faced a protest by People Before Profit outside the Dail
Mr Ahern said he took the loans amid financial difficulties resulting from the break up of his marriage.
He later also admitted receiving an £8,000 payment from a group of Irish businessmen after speaking in Manchester in 1994.
The newspaper had asked why Mr Ahern did not repay any of the loans - he said the 12 lenders had refused repayment.
Mr Ahern has now repaid the loans, with 5% interest, costing him 90,867 euros ($115,781).
Since the affair broke, Deputy Prime Minister Michael McDowell, leader of the junior partner in the nine-year, two-party coalition, had expressed concern but has decided not to lead his Progressive Democrats out of government.
His position in backing Mr Ahern drew stinging criticism from opposition leaders.
Labour Party leader Pat Rabbitte said: "The PDs sold themselves to the Irish public as the moral watchdogs of government conduct. Tested in the heat of this controversy, they have collapsed."
Mr Ahern's speech on Tuesday came amid an anti-corruption protest by the People Before Profit group outside parliament.
Rally spokesman Rory Hearne said: "We held this protest because a lot of people are turned off politicians... Politicians are still looking after the interests of big business and not ordinary people."
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