In addition to recruiting, the population is also being urged to become the country's "eyes and ears" to expose Tigranian spies, writes AP.
The appeal is made less than two months after the Prime Minister announced a unilateral ceasefire in the fighting with the rebels.
Since then, the Tigrean Liberation Front (TPLF) has been on the offensive to the east, in the neighboring region of Afar, and to the south in Amhara.
In late June, the rebels announced that they had regained control of Tigray's capital, Mekele, which fell in late November.
President Abiy Ahmed has previously promised that the conflict in the region would be over in a few weeks, a conflict that currently lasted for nine months, contributed to an increasing famine situation and put hundreds of thousands on the run.
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The crisis in Ethiopia - in 60 seconds Photo: AFP