Toby Young has resigned as director of the New Schools Network, the charity which supports groups wishing to set up free schools.
In a statement published on the NSN's website this afternoon, the organisation's trustees said: "Toby has concluded that the media attention his continuing presence at the helm of NSN is attracting has become a distraction from the vital work it is doing and, for that reason, he has decided to step down."
"The trustees will be announcing the appointment of an interim director in due course. The trustees are grateful for Toby's work during his time here and wish him well in his future endeavours."
Mr Young became the focus of controversy earlier this year because of his short-lived appointment as a board member on the Office for Students - the government's new universities regulator.
The appointment was criticised when it came to light that he had written articles praising "progressive eugenics" and mocking the inclusivity agenda, as well as posting crude comments on social media, including about women's breasts. Mr Young was forced to stand down from the OfS nine days after his appointment was announced.
The appointment was subsequently criticised by the commissioner for public appointments, who said the government's due diligence had been "inadequate", and that the process had been conducted in a manner which compromised "the principle of fairness".
The NSN is currently awaiting the outcome of bids to deliver two Department for Education contracts, and there has been speculation that the controversy surrounding Mr Young could have resulted in the charity losing its government funding.
Mr Young said: “NSN is a wonderful charity and it has been a great honour to serve as its director."
He added: "NSN has worked with over two-thirds of the 691 free schools that have opened or been approved to open so far and the charity will, I am sure, remain at the heart of what is proving to be the most successful education policy of the post-war period."