Sunil Mittal, the billionaire-founder of Indian telecom operator Bharti Airtel, is in advanced talks to buy a 49 per cent stake worth $2 billion in the Indian unit of Chinese consumer electronics maker Haier, Bloomberg News reported on Friday. Mittal has partnered with private equity firm Warburg Pincus to buy the stake, and a deal could be signed in a few weeks, Bloomberg reported, citing people familiar with the matter. The talks are ongoing and Haier may decide not to sell, while other