Two senior FBI witnesses will attend the hearing of preliminary issues in the trial of Mr Michael McKevitt, the alleged leader of the "Real IRA", the Special Criminal Court was told yesterday.
Prosecuting counsel Mr George Birmingham SC said that six witnesses who have sworn affidavits, including two from the US, would be required for the preliminary hearing on October 8th.
The court has been told that the US witnesses were the assistant director of the counter-terrorism section of the FBI and a FBI field officer.
The witnesses would be required for the hearing of preliminary legal argument over the disclosure of documents to Mr McKevitt's defence team.
Mr McKevitt's counsel, Mr Hugh Hartnett SC, said that an issue is expected to arise over the editing of hundreds of the 3,000 documents which have already been disclosed to the defence.
He said the court may well have to examine the edited documents.
Mr McKevitt was served with a writ in Portlaoise Prison in July by the families of the 29 people killed in the "Real IRA" bomb attack in Omagh in August 1998. Another four men are also being sued for damages by the families in a civil action before the Belfast High Court.
Mr McKevitt's trial at the Special Criminal Court is due to go ahead early next year and is expected to last six weeks.
The court was told at an earlier hearing that the main prosecution witness in the trial is Mr David Rupert, who worked for the FBI and British intelligence, and that he was observed by gardaí meeting Mr McKevitt on a number of occasions.
The court also heard that he successfully infiltrated the "Real IRA" leadership and attended its army council meetings.
The court has also heard that Mr McKevitt allegedly met Mr Rupert over a two-year period and asked him to acquire equipment for the dissident republicans.
Mr Michael McKevitt (51), of Beech Park, Blackrock, Dundalk, Co Louth, is charged that between August 29th, 1999, and March 28th, 2001, within the State, he was a member of an unlawful organisation styling itself the Irish Republican Army, otherwise the IRA, otherwise Óglaigh na hÉireann, and that he directed the activities of the same organisation.
It is the first case for allegedly directing terrorism brought under new legislation brought in after the 1998 Omagh bombing.
Anyone convicted of the offence faces a maximum sentence of life imprisonment.