The Nigerian National Petroleum Corporation (NNPC), has increased the pump price of petrol by N4 at its mega stations, thereby changing the price from its initial N141 to N145, per litre. NNPC prices have been N141 in the last few months until on Tuesday Nov. 2, when it was raised to N145.Reacting to this, spokesman for the NNPC, Garba Deen Muhammad, told Daily Trust; "there was no rule that compels any marketer including the NNPC to sell at a particular price. A price regime was introduced between N135 and N145. So, you can sell anywhere within that range. What you are seeing is interplay of market forces."