Government, private firms and wheat

BS writes in an edit

The large corporations who are participants in the wheat trade have been informally requested by the Central government to not buy wheat from Punjab and Haryana. The context is that last year, firms like Cargill and ITC had bought up roughly 1.3 million tonnes, or 17 per cent, of Punjabs wheat output, by paying Rs 20 per quintal more than the price offered by the government. The legitimacy of the governments request is suspect, and various industries (cement, steel) have demonstrated in recent weeks that they are not about to panic because the government frowns on their pricing or other decisions. Everyone knows that the government has the power to order tight stocking limits for essential commodities thus forcing wheat supplies into the market. Still, can and (perhaps more important) should the government come in the way of a private transaction between two citizens of India?