Delhi Transport Minister Gopal Rai on Thursday said levy of congestion tax would help solve the problems of increasing pollution and gridlocks in the national capital.Delhi was "inching towards it (congestion tax)", he said while talking to journalists in West Delhi's Dwarka on the preparations for a 'Car Free Day' in Delhi on November 22."We will have to plan it (congestion tax). It will have to be done. Awareness cannot be the solution... enforcement will have to be in phases," Rai said.The Delhi government is not the first to mull over congestion tax system that has proved successful in London, Milan, Rome as well as the Scandinavian countries.In 2011, the then Congress government toyed with the idea but the plan never took off.