The Government invited over 2,800 reservists to the annual week-long snap "defense readiness exercise" OKAS/QUILL 2023 on Thursday.
The purpose of the exercise is to practice the functioning of the reserve army, the Ministry of Defense said in a statement.
"There is no direct security threat to Estonia," it added.
OKAS/QUILL tests the national chain of command, from the Estonian Government decision down to the combat readiness of specific units in the rapid response structure. It will take place from September 22-28.
The Estonian reserve-based defense model requires reservists to be ready to react and participate in exercises at all times, the ministry said.
This year, 2,861 reservists from the 11. Infantry Battalion, the 16. Air Defense Battalion and the 42. Northeastern Territorial Defense District of the Defense League will take part.
Reservists whose units are called to the exercise are required to report immediately to the designated assembly point.
The exercise takes place every autumn and participants are called up with no prior notice.
The Estonian Defense Forces regularly gather reservists for exercises with 120 days' notice, such as HEDGEHOG (SIIL) and SPRING STORM (KEVADTORM).
Editor: Helen Wright