the United States has designated Nigeria's Boko Haram and Ansaru militant groups as foreign terrorist organizations, reports the BBC.
The state department described the move as "an important" step to help Nigeria "root out violent extremism".
It means US regulatory agencies are instructed to block business and financial transactions with the groups.
Boko Haram wants to impose Islamic laws in northern Nigeria, and has been blamed for thousands of deaths. Ansaru is seen as an off-shoot of Boko Haram.