The Oireachtas Banking Inquiry is in discussions with the Director of Public Prosecutions about the possibility of compelling certain former directors of Anglo Irish Bank and Irish Nationwide Building Society to appear before the committee as it moves into the so-called Nexus phase of its work.

It is understood that the inquiry wants to call a number of the key figures at Anglo and INBS before the crash but has to be careful not to cut across legal proceedings being pursued by the DPP in relation to the extraordinary events that led to the institutions being bailed out by the State to the tune of €35 billion.

Questions have been raised about the committee’s ability to investigate certain matters relating to Anglo and INBS that are subject to legal cases involving the DPP.

The committee is conscious that any legal challenge to its work could stymie its examination of the financial crisis and is determined that the inquiry will not be brought down.

To date, 29 people have been compelled to appear during the Nexus phase, which will begin on April 22nd. This includes 16 current or former bankers connected with AIB, Bank of Ireland and Ulster Bank. None of the main figures connected with Anglo, INBS or Irish Life & Permanent has so far been compelled to attend.

It is understood the committee has left slots free in the second half of July to accommodate the possible appearance of former Anglo or INBS executives. Given that notifications have to be sent out eight weeks in advance of an appearance, this means the inquiry will have to compel former Anglo and INBS executives to appear by mid May.

The committee is preparing to sit each Wednesday and Thursday from late April to the end of July, holding four hearings a week. It will break for August before returning in September to conclude its hearings. A report will be finalised by November.

The inquiry said yesterday it had stepped up security around the 30,000-plus documents that it had received from various banks and institutions in recent months. Committee chairman Ciarán Lynch declined to put a cost on the increased security. He said it was within the overall agreed budget for the inquiry’s work, which has been reported at about €5 million.

The Nexus phase will involve the committee engaging with institutions and individuals who had roles relating to the financial crisis. It will focus on three broad areas – banking systems and practices; regulatory and supervisory systems and practices; and crisis management systems and policy responses.