The owners of the giant Grangemouth oil refinery have been accused of “cynical blackmail” after workers were told to accept new contracts or have the changes imposed on them.
Unite said the move by Ineos amounted to a “sign or be sacked” ultimatum, adding it was considering legal action over the move.
Letters were sent to the homes of workers at the Scottish site, setting out a number of changes to terms and conditions.
The letter spelt out changes including ending the final salary pension scheme, freezing pay and bonuses, reducing shift allowances and new agreements with unions, including having part-time convenors.
“We expect to seek individual employee agreement to the final changes, and, where agreement is not forthcoming, to implement the changes in due course by issuing notices of termination and offering new contracts of employment to those employees which incorporate the new terms,” it said.
Unite said workers were being told to accept the new terms and conditions by 6pm on Monday.
“This is cynical blackmail from a company that is putting a gun to the heads of its loyal workforce to slash pay, pensions and jobs,” said Pat Rafferty, the union’s Scottish secretary.
“Menaces and threats will not secure the future of Grangemouth which now rests in the hands of a few faceless unaccountable shareholders.
“We will not allow such an important national asset to be held to ransom and urge Ineos to drop the blackmail and engage meaningfully with the workforce over a transitional agreement.”
Unite, which has called off a planned 48-hour strike from Sunday, accused Ineos of “fancy accounting manoeuvres”, and challenged the firm’s statements about the financial difficulties it faces.
Ineos said it was going directly to the employees rather than deal with Unite, amid fresh clashes over the company’s finances and its decision to close down the plant.
“This is D Day for Grangemouth,” said Calum MacLean, Ineos chairman.
“The shareholders have expressed extreme concern that the industrial action over recent days has cost the site £20 million at a time when losses are already £10 million per month.
“The site cannot afford this – hence the urgent need for employees to decide to support the company.
“If we can get the changes we want, the company has committed to investing a further £300 million in the site which will help secure its long-term survival.”
Ineos said the Grangemouth refining and chemicals complex had only been shut down twice in the last 40 years – during a previous Unite strike in 2008, and again in preparation for the latest walkout.
A statement said that immediate restart of the complex would pose a safety hazard.
“The Grangemouth site is three times the size of the city of London and it is an incredibly complex system of manufacturing plants all connected by miles of pipes carrying highly flammable materials.
“Shutting down the site and restarting again is not like switching the lights off and on. It takes days to shut down properly and it takes weeks to bring it back up again.”
Meanwhile, Scotland’s First Minister Alex Salmond left his party’s national conference in Perth to hold talks with the two sides amid the escalating row.
“Governments can’t make agreements” in such disputes but can “encourage the circumstances in which agreements can be found”, he told party delegates.