French rail unions on Thursday called a wave of strikes, setting up a confrontation with President Emmanuel Macron as he tries to push through an overhaul of the state-run rail operator.

Reforming the debt-ridden state-run operator SNCF has long been a political hot potato in France. A previous bid in 1995 sparked paralyzing strikes that forced the government to climb down.

The strikes planned from April 3 could be the one of the biggest challenges to Macron's reform agenda since he took office last year.