SIPTU has deferred today's strike at some Tesco stores pending a Labour Court investigation. The union, which represents about 600 members at stores in Athlone, Cavan, Edenderry, Mullingar and Portlaoise, has rejected new pay scales which, it claims, could leave staff doing the same work earning £16 a week less than staff in other stores. MANDATE, which represents most of the 7,000 Tesco employees in the State, has already negotiated a new salary structure with pay increases of between 10 and 20 per cent. The agreement consolidates 42 existing rates into two new rates. These are due for review in two years but SIPTU wants a single rate struck now, plus shift payments for unsocial hours.