There are concerns over a possible chocolate shortage this Christmas after workers at a cocoa and chocolate factory supplying Ferrero Rocher voted to go on strike over pay and conditions. Staff at one of Britain's biggest suppliers of cocoa products to the chocolate industry are unhappy.

Ferrero Rocher hazelnut chocolates are made with products supplied by Cargill Cocoa & Chocolate works in Worksop, Nottinghamshire, where the GMB union is at loggerheads with bosses. The union says that industrial action could choke off chocolate supply over the critical Christmas period, reports The Mirror. The company says that it has made a fair and competitive pay offer and that they do not expect problems with the supply of chocolate.

The gold foil balls, famous for their 'Ambassador, you are really spoiling us' ad, have been a favourite in British homes for decades. First introduced into the UK in 1982 by Italian confectioner Ferrero, there is much secrecy surrounding production of the chocolates, named after a grotto in Lourdes, France, where miracles are said to take place.

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GMB organiser Cameron Mitchell said: "The spectre of Christmas without this beloved Yuletide treat would be devastating. That’s exactly what’s on the cards if company bosses don’t act urgently to avoid strike action.

"Workers aren’t demanding gold-wrapped payouts - instead they’re asking for a pay packet that covers the bills. We urge company top brass to urgently get back around the table with a fair offer for our members."

As well as Ferrero Rocher, Cargill produces chocolate for Veliche Belgian chocolate and confectionary decorations company Smet, according to its website. The Mirror has contacted the company for comment.

The GMB said: "Workers rejected a real terms pay cut at the confectionery giant’s site in Worksop, Nottinghamshire. One hundred per cent of workers balloted, voted to back strike action, with dates for the walkouts to be announced in the coming days."

A spokesperson for Cargill said: "After unresolved discussions with trade union GMB over an unrealistic final demand of a 10% increase and £1,400 one-off payment for employees, employees at Cargill’s Worksop facility have threatened to strike.

"Cargill has made a fair and market competitive offer to its employees of a 5.5% increase, plus the £1,400 one-off payment. We greatly value our employees and the work they do and are disappointed we have not yet come to a collaborative agreement with the union.

"As we continue to facilitate meaningful discussions, we ask for your understanding that we do not currently want to issue any further comments."

A further statement from Cargill reads: "The GMB union at our Worksop facility in Nottinghamshire has taken a vote to confirm their intent to strike. At this time, however, employees are not on strike-operations continue as usual and employees are on the job. Cargill has contingency plans in place to continue providing chocolate to our customers if a strike does occur. We do not currently have, nor do we anticipate, a chocolate shortage or adverse supply chain impact to any of our customers.

Regarding pay negotiations, we can confirm Cargill has made a market competitive offer of a 5.5% increase, as well as an £1,400 one-time bonus payment, as we greatly value our employees and the work they do. Twelve of our 34 employees at Worksop belong to the GMB union and we hope we can come to a collaborative agreement."