An independent group is to investigate the shipping company, ownership and insurance relationships, lawmakers agreed.
The task force is to present its findings within a year and a half, the justice ministry said.
New information could lead to a resumption in police investigations.
The Scandinavian Star caught fire on April 7, 1990, as it travelled from Oslo to Frederikshavn in northern Denmark.
Of the 480 people on board, 159 lost their lives.
Investigations revealed that fire had broken out in several places and was likely due to arson. However, this was never conclusively clarified.
Relatives of the victims have criticized the investigations, arguing that the fire was caused by attempted insurance fraud.