Officers from An Garda Síochána could be asked to give evidence at the inquest for missing Northern Ireland schoolgirl Arlene Arkinson, a coroner's court has been told.
The long-running case, which opened 13 months ago, has stalled over a wrangle for information from authorities in Dublin.
The court is waiting for documentation about the garda investigation into the 15-year-old's disappearance in 1994.
A lawyer for the Arkinson family told a preliminary hearing at Belfast's Laganside Court that once the documents have been received, gardaí could be asked to give oral evidence to the inquest.
Due to the different jurisdictions however, gardaí cannot be compelled to attend.
"We will have to decide if oral evidence from gardaí is necessary. More critically, would any be forthcoming?" the lawyer said.
He told the coroner: "The problem is, some of these matters aren't in your power or control."
Arlene, from Castlederg in Co Tyrone, vanished after a night out across the border in Co Donegal in August 1994.
She was last seen being driven down a country road by convicted paedophile and child-killer Robert Howard.
Despite extensive searches, including a dig late last year, the teenager's remains have never been found.
The coroner's court has requested documentation from Irish authorities in relation to four key areas.
These include the lines of inquiry pursued by An Garda Síochána; searches carried out south of the border; and a purported meeting between gardaí and Howard's former girlfriend Patricia Quinn and her daughter Donna Quinn in Letterkenny.
A lawyer for coroner Judge Brian Sherrard told the hearing that a "comprehensive response" from the Chief State Solicitors Office in Dublin was "imminent".
Judge Sherrard said the news was "very reassuring".
He stressed the importance of obtaining the material, but warned it "may well be that nothing of great value emerges".
Delays in progressing the inquest into Arlene's disappearance are continuing to leave the Arkinson family "extremely frustrated," their lawyer told the coroner.
He said: "We have reached what we hope is the start of the end. But we have been thinking we are at the start of the end for quite a few months.
"The frustration here is not what is being done here in Northern Ireland, but comes from outside."
The case has been adjourned until 27 April.
Judge Sherrard said he hoped that on that date, the requested documentation from the Irish authorities will have been received.
The Arkinson family, who have closely followed court proceedings, were not present for the hearing.
Robert Howard was acquitted of Arlene's murder in 2005 by a jury that was not told of his lengthy criminal past, which included the murder of south London teenager Hannah Williams several years earlier.
However, he remained the prime suspect in the Arkinson case until his death in prison in 2015.