Adecco shares lost more than a third of their value yesterday after the world's largest temporary staffing company said it would delay release of its 2003 financial results following question marks over its accounting procedures.

The shares were down 35 per cent in Zurich after the Swiss company said it had appointed an independent lawyer to conduct an investigation.

"It's serious and it will take time until it is worth investing in it again. But I wouldn't say it was another Parmalat," said Mr Ronald Wildmann at Bank Leu, referring to the accounting scandal at the Italian diary group.

Adecco said the reasons for delaying its results included "the identification of material weaknesses in internal controls" in its North American operations of Adecco Staffing, and "the resolution of possible accounting, control and compliance issues" in certain countries.

The company was seeking to determine the impact of these issues on its results for the year to December 28th, which were due on February 4th.

It said it could not yet predict when the results would be published.

Analysts said Adecco's refusal to comment further, citing legal reasons, meant it was hard to gauge the extent of the problems. "The best case is that it is only North American Adecco Staffing, which accounts for about 4 per cent of profits and where the only problem I could envisage is with provisioning," said Mr Wildmann, after downgrading the stock from buy to sell.

Dresdner Kleinwort Wasserstein analysts wrote that the announcement was "as bad as it gets".

They speculated Adecco's acquisition in 2000 of Olsten, which was primarily focused on the US, could be unravelling. - (Financial Times Service)