The Charity Commission has opened a statutory inquiry into the Durand Education Trust, a charity connected to a London academy school, amid concerns around the business interests of its £400,000-a-year head teacher.

The Commission also cited concerns about the management structure between the charity and the Durand Academy, as well as oversights in asset investment.

The inquiry will reportedly investigate three key areas of the relationship between the trust and the academy, these being: whether or not current or former trustees properly “discharged their duties”, whether or not conflicts of interest were properly identified and adequately managed and whether or not the management of the charity has been mismanaged generally.

The commission has been aware of possible problems with the trust since October 2014. Earlier this year chief executive Paula Sussex told the Public Accounts Committee that the opening of a statutory inquiry was likely.

The charity was also investigated by the National Audit Office in 2013, which uncovered evidence of a “large number of conflicts of interest” involving the school's head, Sir Greg Martin.

In addition to his £229,000 remuneration package, Martin was paid £161,000 as the sole director of a leisure centre that operates from the school site.

Concerns have also been raised over a dating agency formerly run by Martin which is registered to the school's address.

Martin admitted to the public accounts committee that he was being paid nearly £400,000 a year as the Academy’s head teacher, a figure that reportedly left Margaret Hodge MP, chair of the committee, “gobsmacked”.

According to the Durand Education Trust’s accounts, which were filed in early January, its close relationship with the Durand Academy trust precludes the need for it to register with the Charity Commission.