Britain ordered the release on Sunday of hundreds of secret documents relating to the 1989 Hillsborough football stadium crush which killed 96 people.
The interior ministry said Home Secretary Jacqui Smith wants a 30-year secrecy rule waived to allow police and public body documents on the tragedy to be published 10 years early.
"The home secretary has asked for all documents to be released," a spokeswoman said.
Ninety-six Liverpool soccer fans died in the crush during the 1989 FA Cup semi-final tie with Nottingham Forest, at the neutral Hillsborough ground of the Sheffield Wednesday club.
More than 20,000 people gathered at Liverpool's Anfield stadium last Wednesday for a ceremony to mark the 20th anniversary of the tragedy.
The disaster and a subsequent inquiry changed the way soccer crowds watch the game by introducing all-seater stadiums and prompting the removal of fencing at the front of stands.
Survivors and victims' families have been fighting for a fresh inquest to be held, unhappy at the decision by the coroner at the original 1991 inquest to limit the scope of his review.
They also accuse police of a cover-up and of trying to place the blame on supporters' behaviour.
Kevin Robinson of the Hillsborough Justice Campaign group welcomed Sunday's decision, but said families now also needed a full public inquiry.
"People have a right to know what happened to their loved ones," he told BBC television.
"Their loved ones went to watch a game of football and never came home. And for 20 years we've been campaigning to get that information out. That's the least that can be done."
Smith's move comes after Andy Burnham, minister for culture, media and sport, used Wednesday's anniversary to urge police and ambulance services, as well as the local Sheffield council, to publish all material to help families establish what happened.
"The Hillsborough families have suffered the immediate pain of the tragedy and the anguish afterwards of 20 years without a sense of proper resolution or closure," he said in a statement.
"There is a case for full disclosure by any public body of any document ... which would shed light on the disaster and its aftermath. It is vital that we have transparency."
(Reporting by Kate Kelland; Editing by Sophie Hares)