French unions have reacted with fury to what they say are plans by the Fonderie (foundry) du Poitou Aluminium (FPA) to slash wages by 15%.

The foundry - which mainly produces engine cylinder heads for Renault, BMW, Citroen and Peugeot among others - is owned by Groupe Montupet and is based in Vienne some three hours South-West of Paris.

But the CFE-CGC union is claiming the company wants to impose a draconian 15% wage cut in order for the foundry to remain competitive with other Montupet sites in France, namely Laigneville and Chateauroux.

"This [reduction] is not enormous, it is unbearable," a CFE-CGC union representative in Vienne told just-auto. "Imagine two months ago we negotiated [a] 1.5% increase in salary - today we have been asked to reduce our salaries by 15%.

"I don't know any business that would accept a reduction of salary and which has survived two years afterwards. [This] 15% is the first time in France that a group asks its employees to lower salaries by 15% - it has never been done. The management of Montupet is going too far."

The union says FPA was formerly run by Renault before being acquired by Montupet at the beginning of last year and is calling on the new management not to compare French wages with those of Eastern Europe or Mexico.

"We were with Renault for - I don't know how many years," said the CFE-CGC union representative. "How is it Montupet salaries are 15% less [than] FTP?"

The union is also outraged by the wages proposals happening in "full summer" and claims there could only be two possible outcomes on employees' return from holiday: redundancy or signing a new contract with the 15% salary drop.

"Does Montupet really intend to let FPA live?" added the CFE-CGC.

The foundry employs 571 staff with the CGT and Force Ouvriere unions also present in the factory.

Neither FPA in Vienne or Montupet in Paris were immediately available for comment.