Gandhinagar: Real-estate developers and contractors from across Gujarat will observe a day-long nationwide strike on Friday to protest against the “undue hike” by companies in prices of cement, steel, diesel and bitumen in the last one year by forming cartels. Such uncontrolled price hike in raw material could push the construction costs by 15-25 per cent, the developers and contractors fear. While cement prices are up by 20-25 per cent, prices of steel are up by whopping 40 per cent. Builders’ Association of India (BAI), Gujarat Contractors Association (GCA), CREDAI Gujarat, GIHED and Association of Consulting Civil Engineers (India), Gujarat have given and supported strike call. The associations opin that higher price of cement in Gujarat as compared to other states is unreasonable as Gujarat has presence of number of cement manufacturing plants. The associations want the government to constitute a Cement Regulatory Authority for price regulation.