The Labour government is delaying the release of the Saville Report into the 1972 Bloody Sunday massacre until after the general election.
British troops killed 14 civil rights marchers in Derry.
Ministers received Lord Saville’s report last week.
Relatives of the victims are wary that it could be amended or have parts withheld by government agencies.
John Kelly, whose brother Michael was killed, said, “We cannot allow an open field for the British government to stage and manipulate the release of the report for its own ends.”