The former minister for transport, energy and communications, Mr Michael Lowry TD, and the Minister for Public Enterprise, Ms O'Rourke, will be questioned today at the rail signalling inquiry.
Mr Lowry's successor, Mr Alan Dukes TD, will also be questioned at what will be the final formal session of the inquiry before witnesses are cross-examined by counsel, most likely next week.
The inquiry by a subcommittee of the Joint Oireachtas Committee of Public Enterprise and Transport was set up to establish why the cost of a 1997 signalling programme for lesser-used lines on the Iarnr≤d ╔ireann railway spiralled to more than £50 million despite a £14 million projection.
Work on a parallel telecoms system built on the network for Esat Group, then controlled by Mr Denis O'Brien, was linked to the overrun.
The subcommittee is investigating a number of overlapping relationships between CI╔ and Esat, which was awarded the State's second mobile phone licence by Mr Lowry when he was minister.
The inquiry, chaired by Mr Seβn Doherty TD, has established that the transport group's former director of programmes and projects, Dr Ray Byrne, worked simultaneously for Esat and CI╔. Dr Byrne has said his work for both organisations was not connected.
In addition, the subcommittee has found that an associate of Mr O'Brien, Mr Leslie Buckley, was a director of Esat during a period in 1996 when he was compiling a cost-cutting plan for Iarnr≤d ╔ireann.
Weeks after Mr Buckley completed his consultancy at CI╔, he led the Esat negotiating team that secured agreement with the transport group to build its telecom network on the railway. Mr Buckley has said there was no connection between the work he carried out for Iarnr≤d ╔ireann and for Esat.
He is likely to be asked about the appointment in 1995 of CI╔'s former chief executive, the late Mr Michael McDonnell, and a new management team described as "six of the best". Dr Byrne was in that group.
It is thought that Ms O'Rourke will face questions about a statutory instrument she signed in April 1998, which enabled CI╔ to install the Esat network legally.
