The Dáil disciplinary committee says Mary Lou McDonald abused her parliamentary privilege in remarks about alleged tax evasion.

The Committee on Procedures and Privileges says the Sinn Féin deputy leader should not have named six former politicians - who were alleged to have offshore bank accounts.

Deputy McDonald named the former politicians last December when discussing the allegations of a civil service whistleblower investigating tax evasion by account holders at Ansbacher Bank.

The committee has officially told TDs that Deputy McDonald abused her privilege, and would have been defamatory if she had made the same comments outside the Dáil chamber.