Marks & Spencer investors were today left nursing hefty share price falls after dismal Christmas trading figures brought an abrupt halt to its stock market revival.

Only seven months ago, shareholders were toasting a return to health as shares soared to nearly 750p - their highest level in at least 10 years.

But a 21% drop to 398p at one stage today wiped more than £1.5 billion off the group's stock market value, reversing much of the gains achieved so far in Sir Stuart Rose's recovery programme.

He was appointed in May 2004 to lead a turnaround at the firm, at a time when shares languished at just 280p.

One of his first challenges was to fight off a 400p a share takeover approach from retail rival Sir Philip Green, which appeared to have paid off.

But as shares tumbled back down towards the 400p mark today, investors were no doubt left wondering if the group could again become a target for opportunistic buyers.

Shares in the retail chain have been falling since the beginning of December as fears emerged over the sector's prospects for festive trading, already losing around 15% before today's disappointing third quarter results. But quarterly sales growth had been slowing since summer 2006, as a series of interest rate rises began to knock consumer spending, although shares had yet to react as profits continued to soar.

M&S posted a 28.5% rise in pre-tax profits to £965.2 million in the year to last March 31.

It seemed Sir Stuart had successfully steered the group back up towards the key £1 billion mark for the first time in more than a decade.

An overhaul of its clothing range in a bid to woo back its "neglected" female customers in the key 35 to 55 age range helped keep sales growth above 3% throughout each quarter.

Sir Stuart brought in key talent to drive the clothing revamp, with the George Davies' designed Per Una fashion brand hailed one of its greatest successes.

He commissioned much lauded advertising campaigns, featuring the likes of supermodels Twiggy and Erin O'Connor, which brought M&S back to life on the high street for both food and clothing.

But even Hollywood actor Antonio Banderas failed to see the Christmas ad drive combat flagging Christmas consumer spend and concerns are now raised that this year's profits will miss the £1 billion barrier.

Sir Stuart today shrugged off the share price fall. He said he was "unfazed by what the market thinks", adding that he wouldn't be selling his shares.

The scale of the share price fall comes as many were caught off guard by the sales decline, with analysts forecasting a rise of
1%. Panmure Gordon only last week upgraded M&S stock to a "buy", citing its "defensive characteristics".

Panmure's retail analyst Philip Dorgan today admitted "if we had had our time again we would not have raised M&S to a buy last week".

However, analysts at Numis Securities said that despite the share price falls, M&S was still one of its "preferred plays" within the large cap retailers. It said in a note: "It should benefit from three factors that should provide an artificial boost to like-for-like sales and drive profit growth over the medium term.

"These factors are: store modernisation, long maturity of Simply Food stores and rapid growth in home shopping."
Sir Stuart said he would hold firm with cheaper prices for consumers as the slowdown in spending bites, learning from the mistakes made by the group six years ago.

"M&S got into trouble in 1999 and 2001 because it thought it was immune to a market downturn and we paid the price for three or four years," he said. This time around, he stressed they "will not be compromised" on price.
M&S's shareholders - including around a quarter of a million small retail investors - will be hoping his strategy bears fruit, with the potential for further trading gloom over the next 18 months unlikely to take the pressure off shares anytime soon.