An attempt to close down Turkey’s largest teachers’ union has been thrown out of court in what union leaders and human rights activists are calling a landmark ruling.

“This has to be seen as a victory for all the forces of democracy,” Alaaddin Dincer, general secretary of teachers union Egitim- Sen told The TES.

The case had been brought because of a clause in the union’s constitution that called for children living in Turkey to be educated in their mother tongue.

In July a court ruled that this clause was illegal, and gave the union 60 days to remove it or face a ban. The union had refused to do so, prompting a return to court as the deadline loomed last week.

Several hundred teachers, parents and trade unionists protested outside Ankara’s Second Labour Court while the case was being heard. Inside, human-rights lawyers and representatives from the European Union, which upholds the right to receive mother-tongue education, joined union lawyers.

Advocacy of mother tongue education in Turkey is often seen as support for education in languages such as Kurdish, spoken by the country’s large minority of ethnic Kurds.

Opponents see mother-tongue tuition as threatening the state’s unity and giving in to Kurdish militants, who have long been fighting for independence.

However, union chiefs denied that they were advocating Kurdish separatism and argued in court that their support for mother-tongue teaching was on pedagogical and human rights grounds.

“The case has wider implications because we are arguing that mother-tongue education should be a right all over the world, not just in Turkey,” said Mr Dincer. “This is a basic right for every human being and scientifically justified pedagogically.”

The case threatened attempts to persuade the EU to open talks on future membership for Turkey.

Judge Kudret Kurt ruled that the call to dissolve the union had no legal basis and threw out the case.

“With this, freedom of thought and assembly have passed an important landmark,” said Mr Dincer, though he also warned, “This is not to say that threats like this won’t be made again.”

An estimated one in five people in Turkey are ethnically Kurdish.

The Turkish army is currently conducting its biggest operation in years against Kurdish guerrillas in south-eastern Turkey.