The Samoa Observer reports, CEO of the Justice Ministry, Papali'i John Taimalelagi, saying a "lapse" had been uncovered during a routine review of acts under his mandate.
The Newspapers and Printers Act 1993 drew condemnation from local and international media organisations and practitioners when it was first introduced in Parliament.
It was widely seen as a tool being used by then Prime Minister Tofilau Eti Alesana and the Human Rights Protection Party to curb criticism from the media.
The biggest complaint by media was the requirement in the act for publishers to reveal names of sources under an order of the court.
Papali'i has written to all newspapers "circulating in Samoa" advising of the new requirement.
New Zealand and Australian based newspapers could be required to register under the decree.
Papali'i has given March 1 as the deadline for registration.