Luke Johnson, the chairman of Channel 4, is considering making an offer for FishWorks, the troubled AIM-listed restaurant operator, through his Risk Capital Partners private equity vehicle, The Times has learnt.

The entrepreneur, a former chairman of both the Pizza-Express and Belgo restaurant groups, is understood to have put together a consortium of investors and may already have made a preliminary approach to the board of FishWorks.

Shares of FishWorks, which floated at 33p in June 2005, fell sharply this week after the company said that it was in talks with its bankers over its financial position. It said that a cashflow crisis meant that its future was subject to “material uncertainty”. It also dismissed Ratnesh Bagdai as finance director after less than a year in the post.

The revelations by FishWorks came less than a week after the company issued a business update in which it announced a wide range of cost-saving measures and assured its investors that it remained “confident about the future potential of the business”.

The positive tone of that earlier statement sent the shares 1p higher to 25½p as investors sensed that a recovery from December’s profit warning might be on the cards. However, some shareholders are now calling for the London Stock Exchange to examine whether the group misled the market.

A spokeswoman for the exchange’s AIM regulation department said that she could not comment on specific cases, but added: “We do carefully examine any potential breaches of AIM regulations. AIM Rule 11 does state that companies must disclose without delay any new developments which could effect the shareprice.”

Shares of FishWorks added ½p to 13½p yesterday — up from a low of 10¼p on Wednesday — amid rumours of bid interest.

However, The Times understands that, if it does bid, Risk Capital Partners is likely to pitch its offer below the current price.

Risk, which declined to comment, is already involved in the restaurant sector through stakes in the Giraffe chain, where Mr Johnson is chairman, and Patisserie Valerie, the chain of upmarket French cafés.

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