NEW DELHI: In view of the spike in bitumen prices and shortage of the key raw material for road projects due to prolonged West Asia conflict, highways minister Nitin Gadkari has said that his ministry is considering building cement concrete roads instead of bituminous stretches.Speaking at launch of the country’s first Flex Fuel Vehicle on Thursday, Gadkari said bitumen prices have almost doubled from Rs 45 a kg to Rs 85 and highlighted how domestically produced bio-bitumen can reduce imports and help save foreign exchange. Minister said 30% bio-bitumen produced from rice straw and other biowaste can be mixed with conventional bitumen. Powder of used rubber tyres and plastic can also be added to conventional bitumen for use in road works. In a veiled political message, Gadkari said all waste can be converted to wealth. “Our govt under Prime Minister Modi is there to clear all the waste,” Gadkari said.