Union officials and legal experts in Benin are concerned by the Constitutional Court's decision to back the government's ban on strikes by workers in the defence, security, justice and health sectors, the AFP news agency reports.
It was taken "in the public interest" and for "the protection of citizens", the agency quotes Thursday's ruling as saying. A senior union leader, who asked to remain anonymous, told AFP it was a shocking move and a "hammer blow" for workers.
MPs passed legislation banning public sector strikes in December after a wave of industrial action - but it could not become law until passed by the Constitutional Court.
There have been several anti-government protests over the last few months
Many are angry about some of President Talon's economic reforms
Months of wrangling over the issue between the government and court have followed.
But earlier in June, a close ally of President Patrice Talon was elected to lead the court - a vote that was held behind closed doors, AFP says.
Legal affairs expert Albert Medagbe told AFP the court's backing of the ban was a "worrying sudden legal U-turn".