The Minister for Justice Frances Fitzgerald has said she cannot direct an inquest to be opened into Ireland's oldest missing person case.
Commenting on the case of Mary Boyle, a Donegal schoolgirl who disappeared in March 1977, then aged six, Ms Fitzgerald said it is the role of the relevant coroner to schedule and conduct inquests.
She said her department has no role in the process.
The missing girl's sister, Ann Doherty, has been meeting politicians and has given new statements to gardaí in an attempt to find out what happened to her twin sister nearly four decades ago.
Ms Doherty has alleged that her sister’s disappearance from her their grandparents’ home in Cashelard, Co Donegal has been subject of a cover-up, and that not all evidence was thoroughly reviewed by gardaí as part of the original investigation.
She has previously stated her belief that a prominent local politician was complicit in the alleged cover-up, and says she and her family know who kidnapped and murdered Mary Boyle, who is presumed dead.
In a response to a parliamentary question from Donegal TD Thomas Pringle, Ms Fitzgerald said the case is subject to an ongoing investigation and that she has asked gardaí to keep her updated on any further developments.
With the assistance of investigative journalist Gemma O'Doherty and cousin Margo O'Donnell, Ms Doherty has met Taoiseach Enda Kenny, Fianna Fáil leader Mícheál Martin and other politicians to raise concerns about how the case has been handled.
A 64-year-old man was arrested and questioned in Mullingar in October 2014 in relation to the investigation, but was later released without charge.