The Green MEP, Ms Patricia McKenna, conceded yesterday that the party had been damaged by the disclosure about the make-up of the share portfolio held by its former environment spokesman, Mr Ciarán Cuffe TD.
She said that Mr Cuffe was guilty of not having the "cop-on" to understand that holding shares in companies with questionable environmental records was a "political timebomb".
During a briefing for Irish journalists in Brussels, Ms McKenna was particularly critical of Mr Cuffe for leaving the matter unresolved for so long.
Mr Cuffe has apologised to the party and has promised to review the composition of the portfolio, which he inherited three years ago from his mother.
The disclosure that his €1.3 million portfolio included shares in six oil companies - ChevronTexaco, BP Amoco, Exxon, Schlumberger, Smith International and Unocal - led him to resign as the party's environment spokesman. He also owns shares in the US multinational Sara Lee, a group blamed by environmentalists for paying poor prices to Third World coffee farmers.
Ms Nuala Ahern, the Green MEP for Leinster, said she did not believe that the party had been damaged by the disclosures.