Marks & Spencer has announced that its chairman Paul Myners will stand down from July 2006, following months of speculation about boardroom squabbles.
Lord Burns is a busy non-executive director
Mr Myners will be replaced by Lord Burns, who is currently chairman of Abbey National and Welsh Water.
The announcement of Mr Myners' departure comes after newspaper reports suggested a rift between him and non-executive director Kevin Lomax.
Marks & Spencer is struggling to improve its sales.
Sales were down 4.9% in the 13 weeks to 2 April and the company admitted trading remained difficult.
It was reported that while Mr Lomax wanted to push out Mr Myners, Stuart Rose, the chief executive, wished to continue to work with Mr Myners.
Lord Burns will initially join M&S as deputy chairman from 1 October.
Paul Myners is reported to be the victim of a boardroom rift
He is also a non-executive director of Spanish bank Banco Santander Central Hispano.
A former high ranking civil servant in the treasury, Lord Burns is also a non-executive director of Pearson, owner of the Financial Times, and also of property group British Land.
He has also worked on reviews of hunting, the National Lottery and the BBC.
"The new appointment marks an end to the unseemly haggle over the post," said analyst Tim Green at Brewin Dolphin Securities.