Teachers at Kiviõli High School told Lüganuse rural municipality government that if they do not respond within two weeks to their demands to reinstate the principal they will begin an indefinite strike on January 13.
On Monday, Aktuaalne kaamera reported this is the first time this kind of strike action has occurred in Estonian education.
On December 5 the rural municipality government made the decision to fire the school's principal Heidi Uustalu, which caused protests from teachers and students.
Teacher at Kiviõli High School Mariliis Randmer said: "Every strike, as it is also a precedent in the Estonian state, is an extreme step we do not want to take. Over the course of the next two weeks, we sincerely wish to be involved in the negotiations to find a solution so that we do not have to take this extreme step. Of course, this puts us all in a difficult situation, but maybe we will find a solution very soon."
Of the 47 teachers and social educators at Kiviõli High School, 42 have signed the letter. The potential strike does not involve the school's support staff.
Last week teachers held a one-hour long warning strike in support of Uustalu.
Parish Mayor Viktor Rauam told ERR he would comment on the situation in the new year.
The notice said: "At the session of the municipal government on December 5, it was decided to release Heidi Uustalu, the principal of Kiviõli High School. Teachers and the Board of Trustees have requested the municipality to reinstate Heidi Uustalu as principal. We have been in talks with the municipal government, the education committee, and the council, but our demand has not been met. The meeting held on December 28 also failed to reach a solution.
"Parish Mayor Viktor Rauam said the decision was planned to be resolved by the end of January. We think this is too long and the decision could come sooner. Hereby we are sending the Kiviõli High School Teachers' Strike Notice: If by January 13, the teachers' demand has not been met, or Heidi Uustalu reinstated to the position of principal, we will commence a strike on January 13 which will last until our request is met. During the strike, the school will be run by the school manager.
"In the two weeks leading up to the strike, we are ready to negotiate a solution to meet our demand. Signed by Kiviõli High School teachers."
Editor: Helen Wright