Three Chicago journalists are to seek an emergency court order to prevent alleged "Real IRA" leader Mr Michael McKevitt from obtaining tapes of interviews with FBI informant Mr David Rupert.
Mr McKevitt's lawyers told a Chicago magistrate's court yesterday that the three were in contempt of a District Court order by not handing over the tapes.
A District Court had ruled at 10 p.m. Irish time on Wednesday that the three must hand over the tapes to Mr McKevitt's lawyers.
Mr McKevitt has claimed that he needs the tapes to mount a defence in his trial at the Special Criminal Court on charges of directing terrorism.
Mr Rupert, a prosecution witness, was interviewed by the three journalists as research for a book on his alleged infiltration of the "Real IRA". However, the three journalists, Abdon Pallasch and Robert Herguth, of the Chicago Sun-Times, and Flynn McRoberts, of the Chicago Tribune, refused to hand over the tapes yesterday.
Lawyers for the three are to seek a stay on the order to hand over the tapes until the issue has been appealed to a Chicago appeals court.
Papers lodged with the magistrate's court yesterday said "immediate, irreparable damage" would be caused to the journalists' rights if a stay on the order was not granted.
Lawyers representing Mr Pallasch and Mr McRoberts filed submissions at the magistrate's hearing yesterday in which they requested a quick resolution to the dispute.
They also claim the District Court's order goes against the privilege afforded by both the First Amendment of the US Constitution and an Illinois statute that protects journalistic privilege.