The finance director of Cambridge potato supplier, Greenvale AP, has been convicted of paying £5million worth of bribes to Sainsbury’s buyer, Mr John Maylam, in exchange for securing a £40 million pound contract.

Greenvale AP bribed Mr Maylam with gifts and hospitality between 2006 and 2008, including a £200,000 trip to Claridges, a £350,000 excursion to the Monaco grand prix and hundreds of thousands of pounds in cash.

As a result it is said that Greenvale gained Sainsbury’s valuable business and allegedly overcharged the supermarket by £8.7 million.

The crime was reported by a Greenvale AP accountant, Mr Simon Forster, who became suspicious following requests to withdraw £5,000 bundles in £50 notes from a local bank. Upon further investigation Mr Forster discovered that payments were being recorded as “entertaining” expenses and then written off as “raw materials” or storage costs for potatoes at fictitious firms.

Greenvale’s finance director, Mr Andrew Behagg, denied the allegations claiming that this was a case of extortion. According to Mr Behagg, Greenvale feared that they would lose Sainsbury’s business if they did not comply with Mr Maylam’s demands. However, Croydon Crown Court disagreed with this contention, and Mr Behagg was convicted of corruption.

Mr Maylam and Greenvale’s account manager, Mr David Baxter, had earlier pleaded guilty to corruption and money laundering and will join Mr Behagg to be sentenced on 22 June 2012.

Following Mr Behagg’s guilty verdict, Judge Nicholas Ainley told him: “For any case of this magnitude a sentence of imprisonment is almost inevitably passed, and a significant one at that”.

Head of the CPS Central Fraud Group said: “Today’s message is clear: there is no place for corruption in British business. It attacks fair competitive practices and undermines our international reputation [...] This case demonstrates a clear distinction between reasonable business hospitality and that which is criminally corrupt”.