Financier Mr Dermot Desmond is scheduled to appear before the Moriarty tribunal today to give evidence over his involvement in the Esat Digifone consortium.
The tribunal is investigating the awarding of the State's second mobile phone licence to the consortium in 1996, at a time when Mr Michael Lowry was the minister for transport, energy and communications.
The tribunal heard Mr Desmond made more than €127 million from his involvement in the consortium.