NEW DELHI: With prices of essential commodities rising, Prime Minister Narendra Modi today stepped in and states were asked to take urgent measures to remove hitches in supply chain and ensure "uninterrupted" flow.The Prime Minister took stock of the situation on prices and directed Consumer Affairs Secretary Keshav Desiraju to write to Chief Secretaries of all states to take corrective steps, official sources said. Soon after, Desiraju wrote to the states saying urgent measures at the state level are required to tackle the situation."Needless to say, the rise in prices of onion has been a matter of great concern with the government. Several steps have been taken recently to bring under control the rise in prices of this essential item," he wrote. "The reported spurt in prices could considerably impact the budget of ordinary public. So, urgent measures at the state level are required to tackle the situation," said his letter to Chief Secretaries.The Centre's step came as prices of essential commodities, particularly onion, increased. In the national capital, onions are retailing for Rs 25-30 a kg, while the wholesale price is about Rs 18 a kg.Desiraju underlined that actions need to be taken to eliminate any hitch in the supply chain and to ensure an uninterrupted supply of onion so that the scope for speculation is eliminated and the general public is not subjected to any hardship because of price rise.