Deputy First Minister Martin McGuinness has slammed what happened to the families of the Disappeared as "wrong, unjustifiable and cruel".
He said he watched the BBC's documentary on the Disappeared in which families of some of the 16 people disappeared by the IRA and INLA spoke out about the pain of not just losing their loved ones but being denied their remains.
Seven of the disappeared – Joe Lynskey, Seamus Wright, Kevin McKee, Columba McVeigh, Captain Robert Nairac, Brendan Megraw and Seamus Ruddy – remain missing.
Writing for republican magazine An Phoblacht, the Deputy First Minister said a great deal of information has been brought forward and quoted search co-ordinator Geoff Knupfer as saying the IRA are "trying to help in every way they can".
He said he will continue to make every effort both publicly and privately to see the injustice of withheld bodies brought to an end.
"I make that appeal again to anyone with any information to bring that forward. I understand that these killings happened decades ago and those involved may be dead, may not have been active in republicanism since that time or indeed may well be hostile to Sinn Fein and the peace process.
"But despite these difficulties I do believe that we must continue efforts to see a positive resolution for the families."
He said finding the remaining Disappeared "remains a priority for me and for those of us in the leadership of Sinn Fein".
Sinn Fein president Gerry Adams, who was interviewed as part of the programme, tweeted on Monday evening following the programme appealing anyone with information to come forward to The Independent Commission for the Location of Victims' Remains, the families or himself.
The Independent Commission for the Location of Victims' Remains has asked for anyone with information which might assist in locating the remains of the Disappeared who have not yet been found to come forward.
The commission's confidential free-phone number is +800 5558 5500 and postal address is ICLVR, PO Box 10827, Dublin 2.