The clothing, homewares and food retailer has invited holders of its outstanding 375 million pounds 6.375 percent notes due 2011, and holders of its outstanding 400 million pounds 5.875 percent notes due 2012 to participate in a tender offer on November 24.

M&S said the buyback was subject to it raising new sterling-denominated bond financing on satisfactory terms.

"The purpose of the invitation and the company's contemplated raising of new financing is to take advantage of current favourable market conditions in the debt capital markets and to extend the company's debt maturity profile," said M&S.

A spokeswoman for M&S said the firm was seeking debt maturity beyond 2014.

Shares in the firm were down 0.4 percent at 370.6 pence at 9:57 a.m., valuing the business at about 5.9 billion pounds.

Citigroup , HSBC , Morgan Stanley and The Royal Bank of Scotland are acting as dealer managers for the tender offer.

British American Tobacco , Swedish holding company Investor AB , and French dairy group Danone have all said they plan to buy back bonds.

Bankers say healthy firms will increasingly seek to buy back debt and issue new longer-term paper debt via bond exchanges.

(Reporting by James Davey, editing by Mark Potter)