The energy wing of the French trade union CGT has urged its members to join a nationwide healthcare workers' strike planned for Tuesday.
The union did not say whether the strike would affect power generation.
The state-controlled utility EDF, which operates France's 57 nuclear reactors, accounting for around 70% of its electricity supply, did not comment on whether it had received a strike notice.
The grid operator RTE said in a note on its website that unions at the Gardanne power plants in the southeast, operated by Gazel Energie, were planning to join the strike and that this could affect power production.
(Reporting by Forrest Crellin; Editing by Kevin Liffey)
