Bharti Airtel is considering a bid for MTN, the South African telecommunications group, a move that could bring the Indian company’s biggest overseas acquisition and turn it into one of the most powerful mobile phone operators in emerging markets.

Sunil Bharti Mittal, the company’s founder and chairman, on Thursday night denied that a board meeting on Thursday had studied a proposal for a formal approach. A decision to proceed with a formal offer had not been taken and might never be, he said.