The Attorney General is to apply to the High Court for new inquests into the deaths of the 96 Liverpool supporters who were killed in the Hillsborough disaster.
Dominic Grieve QC told Parliament: "My consideration of the evidence is far from complete but, given the anxiety further delay may cause the families affected by the Hillsborough disaster, I have decided to take an exceptional course and state at this stage that, on the basis of what I have already seen, I have determined that I must make an application to the court.
"In doing so, I should make it clear that further work will need to be done before any application can be made. In particular, there was not one inquest but 96.
"My current view is that I will apply to have every one of those 96 inquests quashed. I believe that these deaths, arising as they do from a common chain of events, should all be considered afresh.
"However, before reaching any final view on the scope of the application, I want to give the families affected the opportunity to make any representations in respect of the family member or members they lost.
"I will therefore be in contact with each family seeking views.''
Grieve said he was determined that the application was prepared "so that the strongest case can be made to the court", adding: "I have given this priority, and will continue to do so."
His announcement came four days after it was confirmed that the UK police watchdog will be carrying out the biggest-ever independent investigation into police conduct in Britain.
The Independent Police Complaints Commission's inquiry will examine the role played by officers on the day of the tragedy and in its aftermath, and could lead to criminal charges being brought by the Director of Public Prosecutions.
Grieve said that any criminal proceedings would have an effect on when new inquests could take place, but would not affect the timing of his application to have the accidental death verdicts quashed.
He added that the cost of the inquests would be borne by taxpayers, and that Home Secretary Theresa May would lead a debate on the Hillsborough Independent Panel's report in the Commons next Monday.
The call for new inquests is the latest development to follow the publication of the panel's report into the 1989 disaster, which happened as Liverpool played Nottingham Forest in an FA Cup semi-final at Sheffield Wednesday's ground.
The report revealed that 41 of those who died could potentially have been saved with a better and swifter response from the emergency services. The original inquests imposed a cut-off time of 3.15pm, with the coroner ruling that the victims had died by that time.
The verdict of those inquests - that the victims' deaths had been accidental - has always been contested by their relatives.
Michael Mansfield QC, representing the relatives, hailed the Attorney General for his "extremely sensible decision" to apply for new inquests and said the original inquests had been carried out "on a false basis".
"Many families have refused to accept death certificates until a proper, thorough and independent hearing takes place," Mansfield said.
Liverpool Walton MP Steve Rotheram said: "This application, if successful, will mean that evidence will be able to be heard after the 3.15pm cut off imposed by the original coroner in the 1989 inquests."
He described the announcement that new inquests will be applied for as "one of the biggest steps forward in the fight for justice for the families in 23 years", saying the original inquests had been "unsound".
In his apology after the panel's report had exposed the truth of what happened at Hillsborough, Prime Minister David Cameron said the original inquests into the deaths were inadequate. The panel's report called the original pathologists' evidence of a single, unvarying pattern of death "unsustainable''.