Bharti Airtel, the largest telecommunications company in India, cautioned Tuesday that its discussions with MTN Group, a Johannesburg-based company that operates cellphone systems in Africa and the Middle East, had not yet led to a firm offer for MTN.

Already, however, analysts and investors are speculating about who might emerge as a rival bidder to Bharti, should that company decide to go ahead with an offer for all or part of MTN. Some of them put Chinese telecommunications companies at the top of their lists.

MTN is highly prized because of its nearly 70 million subscribers and its presence in some of the world’s fastest growing telecommunications markets, including Nigeria and Iran. Analysts say the company could be worth more than $40 billion.

Girish Trivedi, deputy director of the telecommunications practice at Frost & Sullivan for South Asia and the Middle East, said that companies like China Mobile or China Telecom could be “serious contenders” in any battle for MTN. They have deep pockets, government backing and some of the largest subscriber bases in the world, he noted.

So far, a China-India showdown for MTN may be purely a figment of bankers’ and analysts’ imaginations. Spokespeople for the Beijing and Hong Kong offices of China Mobile said they had not heard anything about a bid for MTN. William Li, the Hong Kong spokesman of China Telecom, said that he also had not heard of any plans for a bid.

Bharti Airtel insisted Tuesday that it had not yet made a bid for MTN, despite reports that it had offered $19 billion for 51 percent of the company. “We have just begun talks,” said one Bharti executive briefed on the discussions. “There are many combinations you could look at and any one could work out. There is no offer put on the table.”

The possibility of a takeover bid has lifted the shares of MTN, which closed on the Johannesburg Stock Exchange at 16,000 rand, or $2,121, an increase of 6.7 percent.

Read More ….