The chair of the investigation into IBRC's handling of Anglo Irish Bank loans says that legal issues are preventing him from doing his work.

The Government has confirmed it has received a letter from Judge Brian Cregan in which he said the Commission of Investigation is unable to investigate "any of the relevant write-off transactions" at the centre of the inquiry.

The confirmation comes after the Social Democrats Deputy Catherine Murphy said the investigation by Judge Brian Cregan seemed to be "hamstrung", because it cannot get access to documents held by IBRC.

A report in today's Sunday Business Post highlighted that the judge had told the Government he does not have enough powers to carry out his inquiry.

The investigation was established amid questions about the sale of SiteServ to a company owned by businessman Denis O'Brien.

Catherine Murphy has posed questions to Finance Minister Michael Noonan concerning whether IBRC has released documents to the inquiry.

But she says her questions have been ruled "out of order".

In a statement, Deputy Murphy said, "it is unacceptable that we are almost 5 months since the Commission was instigated and we now discover that it may not have even begun the process of providing answers".

A statement from the Department of An Taoiseach says Enda Kenny has sought legal advice from the attorney general on options that would allow the investigation to be completed.

The statement adds that Judge Cregan is preparing an interim report that will outline the legal difficulties and request an extension of time.