Shares in Trinity Mirror slumped today by 5 per cent when the newspaper group admitted taking a £150 million charge after being forced to write down the asking price for its sport and regional publications.

The publisher of the Daily Mirror will now sell The Racing Post and its regional papers in the Midlands, London and the South East for £450 million instead of the £600 million price tag previously attached to the assets, sending its stock down 26p to 488.5p.

Only three months ago, Sir Ian Gibson, chairman of Trinity Mirror, said it had made "encouraging progress" on the disposals, adding: "We've seen nothing to cause us any worry over the estimates that analysts have put in the market place."

Today, however, Trinity Mirror said: "The proceeds we expect from the disposals will be lower than our original expectations and therefore we reduced the carrying value of our regional newspapers in the Midlands and London and the South East by £150 million."

The newspaper group has been struggling to recover from a tough advertising market in recent years, and total sales for the six months to July 1, 2007 fell by 0.4 per cent to £526.3 million. Group advertising revenues declined by 1.4 per cent to £285.7 million.

Commenting on its outlook, Trinity Mirror said: "Whilst the advertising environment remains volatile from month to month we continue to see improved stability in our advertising markets as the rate of decline slows.

"The board remains confident that our 2007 performance will be in line with expectations."

In spite of falling revenues, operating profits increased by 5.9 per cent to £109.4 million and Trinity Mirror reduced its loss before tax from £186.5 million in the first six months of last year to £70.4 million. In the last six months, the company cut £6 million in costs and expects to have reduced expenditure by £10 million at the end of the financial year and by £20 million by 2008.

Net debt rose by £26.9 million to £467.8 million. Trinity Mirror will maintain its interim dividend at 6.4p.

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