Following a petition by the main opposition Republican People’s Party (CHP), the court ruled late Monday that the law adopted by parliament in March 2014 to close the “dershanes” was unconstitutional.

The text passed by the assembly had ordered the closure of the centers by September 1 this year.

The “dershanes” are very popular in Turkey, with 3,800 of the centers catering for 1.2 million students hoping to win a place in the top schools and universities.

Opponents of the law argued that it would exclude the most disadvantaged students from the most sought-after universities and increase the impact of socio-economic differences on the results of entrance examinations.

Erdogan, who was prime minister at the time, had originally included closure of the centers as part of educational reforms.

However, observers regarded the move as a fresh step in Erdogan’s fight against Gulen’s movement, which controls at least a quarter of the tutoring centres.

The president accuses his former ally-turned-arch-enemy Gulen and his movement of being behind corruption allegations that rocked the government in December 2013 while Erdogan was prime minister and which he has dismissed as a plot by the cleric to unseat him.

Erdogan has vowed no mercy in the fight against Gulen and the authorities have over the last year effectively purged the police force and judiciary to rid them of pro-Gulenist elements.

Gulen leads a broad movement known as “Hizmet” (Service), believed to be supported by millions of Turks and which brings together interests ranging from finance and schools to media.