One of Britain's most famous restaurants has closed its doors after up to 40 diners fell ill after eating there, it emerged yesterday.

Heston Blumenthal took the decision to shut the Michelin-starred Fat Duck at Bray on Tuesday after dozens of customers rang the restaurant to say they had been struck down by a vicious illness which left them with flu-like symptoms, vomiting or diarrhoea.

The wunderkind of British cooking and Channel 4 TV presenter told The Independent he will keep his £130-a-head eaterie closed until further notice, or at least until he can trace the source of the mystery illness or eliminate his premises as its source.

Staff have called hundreds of guests to cancel their reservations. Tests on ingredients for potential food poisoning bugs are due within the next few days, along with virology tests on his 60-strong staff.

An environmental health officer from Maidenhead and Windsor Council has been conducting tests on samples of food, along with a company which Blumenthal took on six weeks ago to routinely test ingredients, Food Alert.

Last night Blumenthal said he had taken the decision to close because he could not bear the thought that his passion, the Fat Duck, had been responsible for making people ill. "Wherever this has come from it's extremely upsetting. It's deeply upsetting," the 42-year-old chef admitted.

"We are going to completely exhaust every avenue we can go down. I don't want another person phoning up the restaurant. It's horrible to hear one person phoning."

He said: "We called in the local council, Maidenhead and Windsor, and an environmental health officer was here on Tuesday and they are very satisfied with all the steps we are taking but we haven't found anything.

"All the tests have come up negative. So it's a complete mystery. I'm not prepared [for the restaurant] to operate until this is done and dusted."

The problems began three weeks ago when customers began phoning to say they had fallen ill after visiting the Fat Duck in the affluent commuter village in Berkshire. The restaurant, famous for dishes such as snail porridge and sardine on toast sorbet, is one of only three in the country with three Michelin stars.

"A few weeks ago, we had calls about people who had fallen ill and you take it very seriously. Also my wife and daughter had a virus and there was something going around. And then we got a few more [phone calls] in and then we stepped up the testing and doing everything in more detail. And then last week we got some more calls and at the weekend we thought, 'We've got to close the restaurant'. "

Blumenthal, whose most recent TV show involved creating a new menu for Little Chef, estimated that between 30 and 40 people had fallen ill.

Closing the restaurant for a week has cost him "tens of thousands of pounds" since the last meals were served at Sunday lunch; the restaurant is closed on Mondays.

Blumenthal said that one theory was that a member of staff may be carrying a virus but showing no symptoms. Test results that have come back so far for up to 14 staff have been negative.

Separately, further tests are being done on the restaurant's food but they are a logistical challenge because dozens of different ingredients can go into a single dish and the Fat Duck receives "thousands" of ingredients from around 30 suppliers.

The restaurant serves several dishes with seafood – a common cause of food poisoning – such as jelly of quail with langoustine and oyster, passion fruit jelly and lavender, but Blumenthal said: "There's no evidence to suggest it's food poisoning.

"I made the decision to make people aware of this because everything has been done completely from the heart and all we want to do is to give pleasure to the customer. We never cut corners on anything and this is the same."