Bharti Airtel, which acquired the African operations of Zain Telecommunications last year, had a net debt of $13.4 billion at the end of the first quarter of the current financial year.
"About 70 per cent of Bharti's debt is on a floating interest rate and 90 per cent of that is dollar debt," said Bhavesh Gandhi, telecom analyst at IndiaInfoline.
The rupee has depreciated against the dollar by around 10 per cent since August.
This would affect interest cost and repayments.
For Bharti, which gets revenue from its African operation, and has payment liabilities, this will have an effect, analysts said.
A Mumbai-based brokerage, which didn't want to be identified, said they'd estimated a hit of Rs 500 crore (Rs 5 billion) on Bharti Airtel's net profit in the second quarter, and a Rs 400 crore (Rs 4 billion) impact on the net profit of Reliance Communications for the the same period, due to the rupee depreciation.
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