U.S. President Donald Trump’s administration in 2017 looked into cutting off public funding for charter schools affiliated with Turkish preacher Fethullah Gülen, whose religious movement the Turkish government blames for the 2016 coup attempt, Bloomberg reported on Monday.

Gülen lives in self-imposed exile in the United States, where his followers run a network of charter schools and associations, and Turkey’s Justice and Development Party government has demanded the preacher’s extradition.

CBC News estimated in 2017 that some 136 Gülen-affiliated schools had been founded in the United States. Some of them have been subject to investigations on suspicion of funding Gülen’s organisation, Bloomberg said.

The inquiry on whether to cut public funding to the charter schools was launched in 2017 before Erdoğan’s first meeting with Trump, Bloomberg said citing two unidentified sources.

The news that Trump’s administration targeted assets linked to one of Turkey’s most wanted men came amid widespread speculation about the U.S. president’s relationship with the Ankara administration.

Trump’s favourable foreign policy stance towards the Turkish government and business links to the country have caused four U.S. senators to question a possible conflict of interest, while news reports have revealed that close aides lobbied for Ankara.

Rudy Giuliani, former mayor of New York, Trump’s personal attorney and lobbyist for Turkey, was involved in the attempt to cut funding to Gülen’s schools and participated in a phone call on their funding, a person who was also on the call told Bloomberg.

Giuliani was at the time pushing for Gülen’s extradition to Turkey, which Ankara has been demanding since Barack Obama’s term in the White House. The former mayor was also pushing for charges to be dropped against Turkish-Iranian gold trader Reza Zarrab, a central figure in a case of sanctions evasion for Iran that involves Turkish government officials and the country’s second-largest state-owned bank.

The charter schools, which focus on science education and take in a large portion of students from low-income households, receive state funding through a federal grant.

But research by a law firm hired by Turkey says that some of the funding is claimed fraudulently and that other illegal and unethical practices take place in the schools.

The Turkish government has paid law firm Amsterdam & Partners $ 1.3 million since 2015 for a campaign to discredit the schools in question, and the firm’s founding partner Robert Amsterdam has accused the schools of immigration fraud, according to Bloomberg.

Following an inquiry by officials on the National Security Council and Domestic Policy Council, the White House suggested the Department of Education investigate the possibility of money laundering through the schools, or whether the schools could be considered to have religious affiliation which would disqualify them from federal funding.

Both options were rejected by the Department of Education, and the department argued that cutting off funding without evidence or violation of grant conditions would violate the Elementary and Secondary Education Act, Bloomberg said.

The schools and Gülen’s movement have ties on the “intellectual or inspirational level,” Bloomberg quoted executive director of the non-profit organisation Alliance for Shared Values Alp Aslandoğan as saying.

Some people involved with the schools including teachers and vendors are alleged followers of Gülen, Bloomberg said, and Gülen has been accused of receiving payments from supporters through donations made by Turkish citizens brought to the United States on special visas facilitated by the schools. Gülen denies the allegations.