Citigroup today offloaded nearly 38 lakh shares of Petronet LNG for an estimated Rs 163 crore through an open-market transaction. Petronet, India's biggest importer of liquefied natural gas (LNG), is registered as a private company. According to bulk deal data available with National Stock Exchange (NSE), Citigroup Global Markets Mauritius Pvt Ltd sold a total of 37,79,753 shares of Petronet. The shares were sold on an average price of Rs 431.73 apiece, valuing the transaction at Rs 163.18 crore, the data showed. However, the buyer(s) of the shares could not be ascertained immediately. Earlier this month, Citigroup had bought 1.05 crore shares of Petronet. At the same time, GDF International, a unit of French energy giant Engie SA, had offloaded 7.5 crore shares, or amounting to 10 per cent stake in Petronet for a little over Rs 3,162 crore.