The Minister for Health Michael Martin is coming under increased pressure from his opposite in the Fine Gael party, Gay Mitchell.
Mr Mitchell is demanding that the Minister clarifies the conflict of interests that has emerged in the investigation of physical and mental abuse within State institutions.
The Laffoy commission has requested an expansion of its powers to allow for an investigation into a vaccine-testing programme that was carried out on orphans.
However, Deputy Mitchell says that the inquiry cannot expand until the Minister makes a full statement concerning the matter.