Ineos chairman Jim Ratcliffe has threatened to close the now Swiss-based petrochemical group's operations at Grangemouth, Scotland - where it operates two crackers, a polyethylene plant and a polypropylene plant - if it does not win concessions from the UK government and the site's unions.

In an interview with Financial Times, Ratcliffe said, "Grangemouth needs cheap feedstocks and a sensible cost structure. If we can't resolve these issues it would need to shut down." The Ineos chairman has been critical of the government for its perceived foot-dragging on shale gas and the unions for failing to accept a reduction of pensions.

The group, which moved its corporate headquarters to Switzerland in 2010 for tax purposes, is currently in discussions with UK authorities about financial backing for a shale gas terminal at the Scottish production site, similar to the one it plans to build at Rafnes, Norway, by 2015.