Marks & Spencer has unveiled bullish growth plans and forecast-beating profits despite further signs of slowing high street spending.

While autumn top-sellers included a black leather dress - worn by Posh Spice Victoria Beckham - and the Autograph clothing range promoted by Take That, like-for-like UK sales slipped to 1.6 per cent in the six months to September 29.

But chief executive Stuart Rose yesterday said he was confident over prospects for a revived M&S as the group posted better than expected underlying profits of £451.8 million in the period, 11.5 per cent ahead of last year.

"Whilst the short term economic outlook remains uncertain, the actions we have taken to reposition and revitalise M&S over the last three years put us in a good position to continue to outperform and give us confidence in the long term growth prospects of the business," he said.

Analysts had been forecasting profits of between £420-450 million, with the consensus averaging £444 million.

Mr Rose also plans to step up investment in the business by pumping in more than £2 billion over two years, including M&S's first store in China by March 2009.

In the UK, M&S felt the impact of the poor summer weather and a major store refurbishment programme as like-for-like growth slowed to 1.2 per cent from July to September.

But the company's shares lifted after the group also cheered investors with a £1 billion share buyback and a 32 per cent dividend hike.

A confident Mr Rose said: "This is a long-haul journey - we may have a little bit of turbulence, we may have to fasten our seat belts, but we're not going to spill any drinks."

The retailer said it had already seen a much improved sales performance from its revamped stores as it heads into the crucial Christmas trading season. Around 70 per cent of its trading space will be overhauled by the end of the year.

Mr Rose, who has drafted in Hollywood actor Antonio Banderas to spearhead a new advertising campaign in the approach to the festive season, added that current trading was satisfactory and described the performance as a "good first half despite a tough market".

Richard Hunter, head of UK equities at Hargreaves Lansdown stockbrokers, said: "Despite a difficult backdrop, these are a robust set of figures, accompanied by some optimistic comments for longer term prospects."

Following the turnaround of the retailer, Mr Rose has turned his attention to expansion at home and overseas.

The company is on track to increase its UK trading space by 4.5 per cent by next March after adding 500,000 square feet in the first half, and has plans for a new distribution base in Bradford to help spur growth. Seymour Pierce research analyst Andrew Wade added that M&S was "surprisingly upbeat".

He said the group's comments on current performance were "a good result given what we have been hearing from the high street about October trading".

M&S is also looking to boost its international sales to up to 20 per cent of group revenues over the next five years - compared to eight per cent currently.

A store in Shanghai is likely to be the group's first entry into the fast-growing Chinese market, while the retailer has also identified India for further growth, and sees opportunities to extend its existing franchise base in Eastern Europe. The group currently has 257 stores in 36 countries.

International sales increased nearly 14 per cent to £320.3 million over the half year, with operating profits jumping 31 per cent to £52.5 million. Overall group sales were up 6.5 per cent at £4.2 billion.

Shares closed up 22.5p at 654.5p.