Mumbai, Oct 1 (IANS) The shares of Bharti Airtel opened strong Thursday despite the firm having to terminate the proposed $24-billion equity-swap-cum strategic tie-up with South Africa's telecom major MTN to create the world's third largest mobile phone firm.

The company's shares opened at Rs.435 Thursday, against the previous day's close at Rs.418.55, and soon shot up to a high of Rs.467, data with the Bombay Stock Exchange (BSE) showed.

Some half-hour into trading, the Bharti Airtel shares were ruling at 445.85, with a gain of Rs.27.30, or 6.52 percent.

Late Wednesday, Bharti Airtel and South Africa's MTN said they were terminating their talks for the proposed deal that could have created a large mobile phone entity, just behind China Mobile and Vodafone Group, with a subscription base of 207 million.

According to Bharti, the proposed deal - which even had the backing of Prime Miniter Manmohan Singh - was called off after the South African authorities declined to accept certain regulatory constraints on the part of both sides.

"This structure needed an approval from the government of South Africa that has expressed its inability to accept it in the current form," said a statement by Bharti Airtel.

"In view of this, both companies have taken the decision to disengage from discussion," said the statement issued after the closing of stock markets in both India and South Africa.

"The alliance planned between Bharti and MTN was a vision based on solid fundamentals, which had the potential of creating an emerging markets telecom giant and the third largest telecom company in the world."