Create a legal ''confidentiality agreement'' that can be used in the UK

Our company ("Bolliger UK Ltd") is employing the wife of a supplier (who's company is called "Euro UK Ltd") to be our accountant. Thus, we need a document for her to sign that says something to the following effect: "I hereby agree that for the duration of my Employment with Bolliger UK, or for 2 full years after the termination of our relationship: neither I or my husband's company (Euro UK Ltd), or any person/company associated to us, will contact any of Bolliger UK's clients and / or suppliers. If I/We do, we accept that Bolliger UK will sue us." I hope that is clear. Please feel free to contact me if you need clarification. Thanks cb