The RSPCA has confirmed the resignation of a third trustee amid claims the charity is being badly run.

Treasurer Karen Harley resigned on Saturday, telling friends she was concerned that "internal wrangling" at the charity could damage her reputation, according to the Daily Mail.

Her departure follows the resignations of two other trustees in the last six months. Christopher Laurence and Sally Phillips who both expressed dissatisfaction at the way the charity is being run in resignation letters seen by Civil Society News.

An RSPCA spokeswoman told Civil Society News the charity “could not comment publicly on reasons for resignations as it is a matter between the trustee and council”. But she confirmed Harley’s departure and thanked her for her “service and contribution to the Society during her time with us”.

The three trustee departures follow a period of upheaval for the RSPCA after Gavin Grant resigned as chief executive for health reasons in February 2014. The charity has been without a chief executive for the two years since – with a trustee David Canavan taking on the role while the lengthy recruitment process roles on.

Last week the Charity Commission told the RSPCA to hire auditors to conduct an inquiry into its governance structure.

A spokesman for the regulator told Civil Society News it had requested the full review to “regularise current governance issues with the charity”.

The announcement marks the second time in 18 months that the RSPCA has been forced to launch a review of its structure.

A Charity Commission spokesman said: "The Commission has regular and ongoing engagement with the RSPCA, as it does with a number of large charities".