PARIS — French Prime Minister Sébastien Lecornu clashed with far-left leader Jean-Luc Mélenchon on Monday over the actions of high school students who are blockading classes and pushing for a nationwide spread of their fledgling protest movement for more resources.

The exchanges in posts on social media between Lecornu and Mélenchon, a top presidential contender, reflected the increasingly combative political climate ahead of a crucial presidential election next spring and amid mounting pressure over France’s finances.

Politicians across the ideological spectrum are seeking issues that resonate with voters. Complaints from students about deteriorating schools, teacher shortages and heavy class schedules have become the latest cause embraced by some presidential hopefuls.

Lecornu, meanwhile, is trying to build enough public and political support to pass a 2027 state budget through a divided parliament, where President Emmanuel Macron ‘s government is besieged by opponents, many of whom are unwilling to accept proposed spending cuts while soaring energy costs and other expenses squeeze households.

Mélenchon, 75, a veteran anti-capitalist firebrand, finished third in the 2022 presidential election and fourth in both 2017 and 2012. The former senator hopes to advance beyond the first round of voting on April 18 and qualify for the May 2 run-off. Younger voters could be key for his chances. Macron is constitutionally barred from seeking a third consecutive term.

Mélenchon defended the school protesters on Monday after Lecornu accused officials from his far-left France Unbowed party of encouraging the scattered demonstrations.

The protests erupted at schools in the Paris area last week, leading to arrests, and spread to other regions. In the southern Alpes-Maritimes region, police arrested 10 high school students on Monday on allegations of setting fires, throwing projectiles and committing other violent acts that injured two students, the regional government said.

Mélenchon accused Lecornu’s government of repressing students with “ferocity” and “an unmistakably racist undertone.”

“Don’t touch our young people,” he posted, urging France Unbowed supporters to become involved “wherever you can.”

Lecornu responded that the racism accusation “is an insult.”

“Students have a right to safety. Staff have a right to protection. Police officers have a right to respect when carrying out their duties,” he wrote. “Condemning the violence and those who attack high school students should require less effort from you than smearing those who protect them. It should be easier than fanning the flames.”