LONDON—Huntsworth chairman Lord Myners has resigned after just six months in the role.

The abrupt exit comes after CEO and founder Lord Chadlington announced his retirement in August of this year, and at a time when Myners is occupied overseeing a review of the controversy surrounding last year's sale of the Royal Mail to the private sector.

There had been charges of a conflict of interest when Myners was selected to lead the review, because Huntsworth agency Citigate Dewe Rogerson provided financial PR support for the deal.

In a statement, Huntsworth said that "an announcement regarding a new chairman will be made as soon as possible."

The company is also searching for a new CEO to oversee its various agency brands, which include Grayling, Huntsworth Health, Citigate and Red Consultancy.

Around 20% of Huntsworth is owned by China's BlueFocus. One of the Huntsworth's senior independent directors, meanwhile, is Terence Graunke, chairman of private equity firm Lake Capital.

Graunke's position has led to speculation of a potential partnership between Huntsworth and Engine Group, which recently sold to Lake Capital.