Relatives of the Bloody Sunday victims are to seek a meeting with the Northern Ireland Secretary Shaun Woodward in a bid to have the report's new publication date brought forward to avoid the run-up to an announcement for next year's General Election.
Lord Saville's findings into the January 1972 shootings in Londonderry have been delayed again and will not be with the Government until 22 March.
The report, which is expected to run to 4,500 pages, is virtually complete but its understood technical difficulties linked to the printing of it is holding up the process - heightening fears among the families that with Easter approaching and the distinct possibility of the UK getting ready to go to the polls, then it could be close to the summer before they get sight of it.
It means it will more than six years after the probe effectively ended and astonishingly 12 years after the marathon process was started by the then Prime Minister Tony Blair in January 1998.
A letter seeking a meeting with Mr Woodward is expected to be on his table within the next 48 hours. A copy of it will also be delivered to Lord Saville, chairman of the £200m tribunal.
Thirteen men were shot dead when Paratroopers opened fire on a civil rights march in Derry's Bogside area. A 14th man, who was among the injured, died later in hospital.
Tony Doherty, whose father Patrick was among the victims, said the families were hugely disappointed and gravely concerned about the new delay.
Downing Street had expected to take delivery later this year, Christmas at the latest, and when ministers do eventually get a copy they are then expected to take two or three weeks, maybe more, to consider the findings before agreeing to go public.
Mr Doherty said: "We will be making our sense of disappointment known to Lord Saville and Shaun Woodward within the next 48 hours, asking them to re-consider the day and bring it forward by a number of weeks.
"March 22 means Parliament will be moving towards the Easter recess and possibly the imminent announcement of an election. That will inevitably mean yet another delay because the Government of the day will want to have a close look at the findings, before the report is finally released to the families. We are gravely concerned about that."
Earlier Mr Woodward, who is in New York and who was told by Lord Saville the report would be with him before the year was out, said he was profoundly shocked.
He added: "I am concerned at the impact on the families of those who lost loved ones and those who were injured. I am equally concerned at the increased anxiety that soldiers serving on the day will suffer."
From The Belfast TelegraphReuse content