Mr Ciaran Cuffe, the Green Party TD, has sold shares he owned in six oil exploration companies, though he has not yet reinvested the money.
The Dún Laoghaire TD came under sharp attack after he revealed the shareholdings in the Dáil's Register of Members' Interests.
Mr Cuffe, who inherited the portfolio from his mother, Patricia, three years ago, instructed his US-based advisers, Brown Investments, some weeks ago to sell the shares.
He had owned $68,253 worth of shares in ChevronTexaco, BP Amoco, Exxon, Schlumberger, Smith International and Unocal - out of a total portfolio worth $1.37 million. He told The Irish Times: "I have sold the shares. But I have not yet reinvested the money. I am looking at ways to make sure that it is invested ethically."
He has already ruled out arms manufacturers, fossil-fuel energy companies, nuclear power firms, or those associated with animal testing.
He also owned shares in the US multi-national Sara Lee, one of the companies blamed by environmentalists for paying poor prices to Third World coffee farmers.
However, the majority of the portfolio, which has suffered major losses over the last couple of years as stock markets plummeted, is held in financial, healthcare and high-technology stocks.
Last month, the leader of the Green Party, Mr Trevor Sargent, pointed out that the National Pension Reserve Fund had not been given any instructions to invest ethically.
The controversy deeply embarrassed the Green Party and led to it demanding that all future candidates guarantee in advance that they do not own shares in such companies.
