NEW DELHI: Congress leader Digvijay Singh has demanded action against Union Minister Nitin Gadkari accusing him of taking several decisions which he alleged were "clear cut cases of conflict of interest and favouritism".In a letter to Prime Minister Narendra Modi , the Congress General Secretary alleged that Gadkari took "undue interest" in raising the blending percentage of Ethanol in Petrol from 10 to 22.5."Nikhil, son of Gadkari, is listed as a Director of Purti Power and Sugar Ltd. Sensing the decision of the government to increase the blending percentage, Purti decided to treble its production from 45 kilo litres to 135 kilo litres per day", he said.Besides he told the Prime Minister that Gadkari "overturned" the ban on electronic rickshaws in the national capital. The Union Minister also announced that potential e-rickshaw buyers will get a loan on 3 per cent interest.The director of the Purti Green Technologies which manufactures e-rickshaws is Gadkari's brother-in-law Rajesh Totade, Singh claimed.Besides, the Congress leader recalled that he had raised the issue of giving Rs 10,000 crore contract for the Jojhila pass tunnel in J and K on a single bid. "When I raised the issue on your intervention, the contract was cancelled".Singh wanted the Prime Minister to take cognizance of all these matters and "take action" against Gadkari."I know you will not act because of political compulsions, but still it is my duty to remind you as the self-proclaimed 'chowkidar' in the national interest...", he added.