The government is likely to mandate blending isobutanol with diesel by the end of this year, Ministry of Road Transport and Highways (MoRTH) Secretary V Umashankar said. This comes after the nationwide rollout of ethanol-blended petrol or E20 petrol earlier this year. Blending diesel with isobutanol, a biofuel, could reduce India's crude oil imports and minimise its carbon footprint.