Disagreements over the blanking out of documents are adding to the delays in an inquest for a dissident republican murdered six years ago.
Kieran Doherty, 31, was shot dead in February 2010 and his body dumped near Derry.
The Real IRA claimed responsibility for killing one of its members, but nobody has ever been charged with murder.
In the weeks before his death, Mr Doherty claimed MI5 attempted to recruit him as an agent and his family have raised concerns the UK security services could have played a role in his death.
At a preliminary hearing, Belfast's Laganside Court was told of significant discord over the level of redaction on five files of papers between legal teams representing the police and next of kin.
Coroner Brian Sherrard described the issue as a "road block".
Addressing members of the family who were seated in the well of the court, Judge Sherrard said: "We are still trying to get a meeting of minds with regards to information that comes before the court."
A hearing to thrash out arguments on the information that can be released into the public domain has been scheduled for later this month.
Meanwhile, the court was also told that officials in the Republic of Ireland have not yet engaged with the inquest process, despite correspondence from the coroner's legal representatives.
Judge Sherrard said efforts to obtain information from An Garda Siochána would have to be stepped up.
He said: "This case clearly has a cross-border dimension. We are going to have to re-double our efforts to see what we can do in other to provoke a substantive response from An Garda Siochána."
After the brief hearing, Vincent Coyle said he hoped the truth about his nephew's killing could soon be established.
He said: "I welcome the judge's decision to re-meet for more discussion.
"Every step forward brings us closer to the truth in these matters."
The case has been adjourned until December 22.