The Prime Minister's Economic Advisory Council (PMEAC) today said rising inflation left Reserve Bank of India with no option but to go in for a policy interest rate hike. PMEAC Chairman C Rangarajan said the RBI will continue to its tight monetary policy stance as long as inflation remains at an elevated level. Rangarajan said that higher interest rates will have an impact on companies' investments as the cost of capital will increase. He, however, exuded confidence that the economy will grow by 8.5 per cent in the current fiscal.