Fine Gael has demanded immediate action from the Taoiseach after Fianna Fail TD Ms Beverly Cooper-Flynn lost here libel appeal in the Supreme Court this morning.
"In the Dáil on February 10th, the Taoiseach said that Deputy Cooper-Flynn was re-admitted to the Fianna Fáil Parliamentary Party on the basis that she had appealed to the Supreme Court," the party said in a statement.
"The Taoiseach now has a responsibility to act swiftly arising from this decision."
Fianna Fáil said it was studying the outcome of today's judgment relating to the politician's lost libel action.
The National Union of Journalists welcomed the court ruling saying it vindicated RTE. Irish Secretary Mr Seamus Dooley said the case underlined the need for urgent libel reform.
He added: "Beverley Cooper-Flynn had an absolute right to seek to vindicate her reputation and no citizen should face possible bankruptcy as a result of exercising a constitutional right.
"The NUJ is currently working with other media groups in campaigning for libel reforms and this case will serve as a reminder of the need for such reforms".
The five members of the Supreme Court were unanimous in the decision to dismiss the appeal.
In the libel action, the High Court found that as a financial adviser with National Irish Bank, she had advised or encouraged people to evade tax.
After a 28-day hearing, a jury decided her reputation had suffered no material injury as a result of RTÉ broadcasts of June and July 1998 implicating her in encouraging people to evade tax by investing money in certain offshore schemes.