An artist's impression of how the new extension could look

The high street retailer has agreed to open a flagship store for Scotland, over four floors, within the redeveloped centre.

Proposals by developers to double the size of Buchanan Galleries have been granted outline consent by the council.

The Scottish Government must give the final approval.

The new Marks & Spencer store would open in 2011 and would replace the retailer's current shop on Sauchiehall Street.

Buchanan Galleries is owned by Buchanan Partnership, a joint venture partnership between Land Securities and Henderson Global Investors.

'Exciting opportunity'

Nick Davis, development director with Land Securities, said: "We are delighted to announce that Marks & Spencer will be moving to a new 150,000 sq ft store once the extension of Buchanan Galleries is completed.

"We are also excited about the opportunity to work with Marks & Spencer and partners to examine options for the existing store in Sauchiehall Street in order to ensure the street retains its profile as a major shopping destination."

The expansion of Buchanan Galleries will include new retail space, an atrium entrance onto Buchanan Street and new bar and restaurant facilities.