Ms Beverley Cooper-Flynn's position as a Fianna Fail TD hangs on whether she appeals her failed libel action to the Supreme Court, following yesterday's awarding of all costs against her.
She faces a legal bill close to £2 million after the High Court ruled she was liable for the costs of everyone in her case against RTE, Charlie Bird and Mr James Howard.
Some Fianna Fail sources indicated last night that her continued membership of the parliamentary party would be under serious threat should she decide not to appeal.
A spokesman for the Taoiseach said Mr Ahern's position remained unchanged from his Dail statement of March 27th. "It is still inappropriate for him to comment on the outcome of the proceedings given that it could be subject to an appeal to the Supreme Court," the spokesman said.
However, on March 27th Mr Ahern refused to give unqualified support to the Mayo TD and described the behaviour the jury found she had engaged in - advising or encouraging people not to pay their tax - as "wrong". If that jury finding was allowed to stand, party sources said last night Ms Cooper-Flynn was likely to have to leave, or be expelled from, the Fianna Fail parliamentary party.
However, Fine Gael and Labour last night called for immediate action, with Fine Gael's Mr Paul McGrath calling on Mr Ahern to "state whether he considers that Beverley Cooper-Flynn TD is a suitable person to be a member of his parliamentary party".
Labour's deputy leader, Mr Brendan Howlin, said the decision "simply confirms what everyone, other than the Taoiseach and Deputy Cooper-Flynn herself, has recognised since the original judgment: that she lost her case". He said the Taoiseach and Ms Cooper-Flynn could not ignore the consequences.
Should she decide to appeal to the Supreme Court, that hearing would not take place until the autumn at the earliest and possibly not until next year. Under the Taoiseach's current position, this would postpone any political action against her for a considerable period, and possibly until after a general election.
A Progressive Democrats spokesman last night echoed the Taoiseach's position, noting that "the issue of an appeal has yet to be resolved".
Ms Cooper-Flynn will not meet her legal team until after Easter, making a quick decision on whether to appeal unlikely. She was out of the State yesterday, believed to be on holiday, and was informed of the costs decision by phone.