new delhi/Mumbai, Oct. 25 -- Global investor Blackstone is set to buy nearly 10% stake in Kerala-based Federal Bank, becoming the latest foreign entity to covet a slice of a domestic bank. The acquisition for close to Rs.6,200 crore will also mark Blackstone's latest bet on India's financial sector, where it has made multiple investments over the years. The private bank's board on Friday okayed issuing warrants to a Blackstone affiliate, to be converted later to a 9.99% stake. Once the Blackstone entity's shareholding reaches 5%, it will get to nominate one non-executive director to the bank's board. Federal Bank said its board has approved a preferential issue of 273 million warrants worth Rs.6,196.5 crore to Blackstone affiliate Asia II T...