Supermarket chain Somerfield said the pace of its recovery had continued to improve after announcing a sharp rise in half-year profits.

The successful refurbishment of stores and a tight control on margins helped the performance, as profits before tax and exceptionals rose to £15.5m in the 28 weeks to November 8, up from £6.4m last time.

But analysts questioned the extent of the group's recovery.

Wise Speke retail expert Anthony Platts said: "Although the results have beaten forecasts, this comes on the back of undemanding comparatives.

"A worrying aspect is that Somerfield is only operating with margins of around one per cent on sales in excess of £2.5bn. Capital expenditure in the first half of the year, to upgrade stores, was around £100m, while operating profit in the period came in at around £17m.

"With only a quarter of the stores having been refurbished so far, it is far too early to say that the UK's sixth largest supermarket chain has turned the corner."

Somerfield executive chairman John von Spreckelsen said he was pleased with the progress, but said that sig- nificant investment, particularly at Somerfield's Kwik Save chain, was still required.

The group has been battling to win back market share after running into problems integrating Kwik Save, which it acquired in 1998.

Last year, it was also the subject of a rejected £594m takeover bid by retail entrepreneurs John Lovering and Bob Mackenzie.