Workers of the Samajwadi Party (SP) on Thursday staged a demonstration at the Master Canteen Square here demanding rollback of the State Cabinet decision to impose additional three-per cent VAT on petrol and diesel.Party State president Rabi Behera said the VAT would influence the price index in the market and fuel price rise of essential commodities.Behera said the additional three per cent VAT, which has increased Rs 1.49 in petrol and Rs 1.33 in diesel prices, would have a cascading effect of 10 per cent to 15 per cent hike on the prices of goods in the market and further burden the common man. He urged the Chief Minister to roll back the extra VAT on petrol and diesel immediately.