Bharti Airtel said late on Wednesday it and South Africa's MTN had called off talks for a planned tie-up due to the inability of the South African government to accept the deal in current form.
Bharti said it hoped the South African government would review its position in the future and allow both companies to re-engage.
Bharti and MTN revived merger talks in May, a year after previous talks broke down over who would control a merged entity. A merger would create an emerging markets giant with more than 200 million customers across India, Africa and the Middle East.
The talks had been extended twice and the present deadline was until Wednesday.
The deal faced scrutiny from regulators and politicians. South Africa is eager to retain MTN's national character and had approached Indian authorities to consider a dual-listed entity, a structure Indian laws currently do not allow.