Independent News & Media is set to announce that it is planning to advertise for a new editor of the country's biggest selling newspaper as its current editor Anne Harris nears the end of her three year contract.

Ms Harris, an award-winning journalist, edited the Sunday Independent from February 2012 after she took over the role from her late husband Aengus Fanning. Under Ms Harris the Sunday Independent's market share on a Sunday reached record heights.

Its sales declined the least relative to its peers and it broke many major stories including revealing tape recordings of Michael Lowry, the former Fine Gael minister, discussing his business affairs.

Ms Harris was previously the deputy editor of the Sunday Independent for two decades. On her appointment the then chief executive of Independent Newspapers Ireland, Joe Webb, said: "Anne is the most innovative, talented and dedicated media professional in Ireland. When she was appointed as features editor of the 'Sindo' in 1985, she set about transforming the weekly offering."

“Not content with just changing the features pages, she very quickly moved on to putting her unique stamp on the entire product. Aengus Fanning recognised her immense talent and encouraged every change, tweak and innovation,” Mr Webb added.

He said her "talent and leadership" led to the Sunday Independent becoming Ireland's best-selling newspaper whose combination of opinion and hard news put it at the "very heart of the national conversation".

INM Group Editor Stephen Rae, the former editor of the Garda Review and the Evening Herald, is expected to announce that he is seeking a new editor of the Sunday Independent later today.

He is currently also advertising for a new editor of the Irish Independent after Claire Grady stepped down from the position after only one year.

It is not known whether Mr Rae will give any detail as to why it has been decided not to extend the contract of the editor of the best-selling newspaper within INM’s portfolio.