Bharti Airtel will issue a statement later on Tuesday on its tie-up talks with South Africa's MTN, a source with direct knowledge of the matter said.
The source did not give details, including the timing of the statement.
Bharti and MTN had 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 deadline for exclusive talks between the two companies runs until Wednesday.