KOCHI: The central government is planning to deregulate the price of diesel and LPG , said C Rangarajan, chairman of the Prime Minister’s Economic Advisory Council .He was speaking at a function organized by the Federal Bank in Kochi on Tuesday.“The government is waiting for an appropriate time to deregulate the prices of diesel and LPG,” Rangarajan said.When asked whether it was possible to bring down the price of petrol by cutting down duties, he said that it would lead to other problems. “We are already committed to a very large level of government expenditure and we need funds for many socio-economic programmes like the employment guarantee scheme. These are programmes which are difficult to run without petroleum duties,” he said.He also claimed the headline inflation would come down in the near future, and said the country should quantify inflation based on the Retail Price Index ( RPI ) like developed nations instead of the Wholesale Price Index (WPI) currently used.“WPI is very often used because the statistics are easily available. Policy makers should use the RPI whenever it is available,” he said.