Petrochemical giant Ineos has accused Unite of trying to lobby their customers Morrisons and Asda in an effort to stop them trading with the Grangemouth plant.
The company is furious union members, currently involved in industrial action, were handing out leaflets outside both supermarkets on Thursday.
Calum MacLean, Grangemouth Petrochemicals (UK) chairman, said: “Unite seems hell bent on trying to close this site. We are losing £10 million a month and desperately trying to stem these losses.
“To go to our customers offices and try and get them to stop trading with us is like turkeys voting for Christmas.”
The ongoing dispute stems from the union’s protest against the company’s perceived mistreatment of union convenor and employee Stephen Deans and the Ineos investigation into his alleged activities which will be completed by October 25.
Mr MacLean said the information on the leaflet was “abusive” and stated: “If this plant shuts, all the blame will be with Unite.”
Unite Scottish Secretary Pat Rafferty said: “It is a peaceful protest, members are not picketing. They are handing out leaflets to customers of the Ineos supply chain about the conduct of Ineos and its unfair treatment of Stephen Deans.
“It is our view Ineos is using Stephen Deans, who is an innocent man, and the country’s energy supplies, as pawns in some twisted industrial game. The company’s inaction will force the union into industrial action which would inevitably put the nation’s fuel supply at risk.
“It will be Ineos’ refusal to engage that will be to blame should this happen.”