Cadbury could find itself facing a strike as 1,300 Unison workers begin to vote over whether to take industrial action against the UK confectionery giant today (18 July).

A union official told just-food that Unison has opened a strike ballot after Cadbury "reneged" on a pay deal that was struck with workers at its Bourneville, Chirk, Marlbrook and Somerdale plants three years ago.

Cadbury had agreed a pay increase of RPI plus 0.5% with the workforce, with a minimum of 2% hike for 2009. However, as RPI in February was 0% the company is instead imposing a deal of 0.5% this year, Unison said.

According to the spokesperson, talks have not been held between the company and the union.

"They provided no reason, no explanation, no negotiation. We can only assume that they have reneged on the pay deal to increase returns to shareholders."

"The workers are angry that while Cadbury's managers and shareholders carve up a hefty 30% leap in profits, made by the hard work of the employees, workers are left choking on the crumbs, a derisory half per cent in their pay packets," Jennie Formby, Unite national officer for the food and retail sector, added.

The union said that, if a strike were to go ahead, it could hit supplies of popular chocolate products, including Wispa, Crunchie, Dairy Milk and Creme Egg.

Workers at the Somerdale site are excluded from the ballot and any potential strike action due to an agreement reached on redundancy pay when Cadbury announced plans to move production to Poland. According to the agreement, the workers forfeit all enhanced redundancy payments if they take any industrial action.

"The pay issue is particularly important for the Somerdale workers because they were counting on the 2% pay increase to enhance not just their last earnings with the company before their factory closes and production goes to Poland, but also to boost their final redundancy pay. They may be being denied a voice in this process but Unite will still fight for the best deal for them," Formby insisted.

The ballot will close on 18 August.

Cadbury was not immediately available for comment.