Turkish President Abdullah Gul has approved a law closing schools seen as a source of income and influence for an Islamic cleric accused by Prime Minister Tayyip Erdogan of trying to topple him.
The move on Wednesday highlights Gul's solidarity with Erdogan, as the prime minister battles a corruption scandal he says has been orchestrated by the cleric, Fethullah Gulen, whose "Hizmet" (Service) network wields influence in the police and judiciary, according to the Reuters news agency.
Education is central to the mission of Gulen's movement, with millions of students attending cram centres to prepare for entrance exams to win limited spots at state high schools and universities.
Tensions between Erdogan and the US-based cleric, formerly allies, have been simmering for years but boiled over in December, when figures close to the prime minister were arrested.
The scandal, which Erdogan has cast as a plot to oust him by a "parallel state" of Gulen's followers, came weeks after the government moved to shut down the schools, worsening the public row with the cleric's followers.
Earlier this month parliament voted to close the schools by September 1 2015, but the move was subject to the approval of Gul, a figure seen by many in Turkey as having been closer to the Gulen movement than the prime minister.
Erdogan, currently campaigning around the country for municipal elections on March 30, has responded to the corruption scandal by reassigning thousands of police officers and hundreds of judges and prosecutors in what his aides have described as a bid to cleanse the judiciary of Gulen's influence.
Gulen's followers say they are the victims of a witch-hunt.