Secondary school teachers have rejected a 5% pay offer, with 70% saying they would back strike action without an improved deal.
The Scottish Secondary Teachers' Association (SSTA) said 80% of its members turned down the proposal put forward by local authority body Cosla.
The negotiations come in the midst of a cost-of-living crisis caused by rising inflation and soaring energy prices.
Cosla declined to comment after being approached by BBC Scotland.
The Scottish government said it was "committed to supporting a fair pay offer for teachers".
