Argentina has issued a decree formally accepting a share of the blame for the failure of investigations into the bombing of a Jewish centre in 1994.
The blast was the worst terror attack in Argentina's history
Eighty-five people died and hundreds were hurt in the Buenos Aires blast.
President Nestor Kirchner said governments had covered up facts, and that the decree established a mechanism for victims to receive compensation.
The masterminds behind the attack have never been identified, but it has been blamed on extremist Islamist groups.
Argentine, US and Israeli officials have all said that Iran is to blame - a charge Tehran denies.
Tuesday's decree formalises an official declaration of responsibility which the Argentine government made in March, before the Inter-American Commission on Human Rights.
The authorities had previously rejected repeated accusations by members of Argentina's Jewish community that the police and governments had failed to carry out a proper investigation, and of deliberate cover-ups.
The government has also pledged to implement measures designed to solve the case and reveal evidence suppressed by the state during the investigation, La Nacion newspaper reports.
Tuesday's move came days before the 11th anniversary of the attack, in which a car bomb ripped through the Jewish Argentine Mutual Association (AMIA).
Last September five people, including four former police officers, were acquitted of involvement because of a lack of evidence.