Unions are calling for an emergency summit and parliamentary debate in a bid to avert strikes at an oil refinery and petrochemical site.
Workers at the Ineos site in Grangemouth started an overtime ban and work to rule in support of Unite convener Stevie Deans.
He was suspended, then reinstated, by the company over allegations linked to his involvement in the bitter row over the selection of a Labour candidate in Falkirk, where he is chairman of the local constituency party.
Unite accused Ineos of trying to “provoke” a strike, which it warned would be “hugely damaging” to the UK economy.
A previous three-day stoppage at the site in 2008 was said to have cost hundreds of millions of pounds in lost production and other knock-on effects.
Workers have voted heavily in favour of action up to and including a strike and Unite officials said they had not ruled out calling for a walkout.
Pat Rafferty, the union’s Scottish regional secretary, said the firm was using the Stevie Deans dispute as an excuse to introduce sweeping reforms, including pension changes, job losses, an end to collective bargaining and worse pay and conditions for new employees.
Unite called for a summit with the company and politicians, and urged the Scottish Government to hold a debate to help prevent the dispute escalating.
The company has warned the site will close by 2017 without new investment and savings in running costs.
Ineos has put forward a survival plan and has asked the Scottish and UK Governments for grants and loan guarantees totalling £150 million.
Ineos said one of its subsidiaries is to close, with the loss of 18 jobs, blaming low-cost imports and a “hostile” trading environment, as well as the “high cost” of products from Grangemouth.