Relative John Kelly called on Shaun Woodward to 'set the truth free'
The families of people killed on Bloody Sunday have criticised the Secretary of State for failing to let them know when they will receive the Saville Report.
It is due to be delivered to Shaun Woodward on the week of 22 March, but the relatives may have to wait at least another two weeks.
They fear it could be amended or have parts withheld by government agencies.
In a statement, an NIO spokesperson said they want the report published as quickly as possible.
John Kelly, whose brother Michael was killed on Bloody Sunday, said the families feared the report "will fall victim to selective leakage and other partisan usage long before the full report sees the light of day."
"The Inquiry process, detailed, meticulous and painful as it was, could become a total mess and travesty in the final few weeks before it becomes public.
"We are calling on Lord Saville to set the truth free, and we are calling on Shaun Woodward to agree that Lord Saville should set the truth free," he said.
A spokesperson from the NIO said the Secretary of State has met with the families on several occasions, and "understands their concerns".
He will continue to make every effort to ensure that publication is fair to everyone involved.
"However the government must also respect its obligations to Parliament in relation to this public inquiry.
"Once we are in a position to outline publication arrangements we will be in touch with the families."
Foyle MP Mark Durkan said the families deserved clarity.
"We can do without interference and manipulation or the suspicion of manipulation by forces within the government order and that's what the families are left with here.
"Shaun Woodward knew what the issues were, he has mishandled this in recent months unfortunately and the families have been left with no choice but to make the statements here today.
Sinn Fein MLA Martina Anderson said consideration for the families must be the primary concern.
"I think its an absolute nonesense what we're hearing from the British Secretary of State.
"They are actually going to hand this over to the MoD in order for it to be perhaps combed through and details which we now know are in the report may not be released to the families."