However, they also acknowledge that agriculture is among the sectors most exposed because fertiliser represents a significant share of production costs. NFUS believes fertiliser prices are the biggest concern. Industry estimates suggest the levy could add anywhere from £10 to £50 per tonne to some nitrogen fertilisers, depending on carbon prices and market conditions. For many arable businesses, where fertiliser accounts for a substantial proportion of production costs, any increase would further squeeze already tight margins. Ms Scott noted that several EU governments had introduced support measures to help offset higher fertiliser costs.