Also, their cumulative external debt had increased to 49 per cent of total debt in 2011-12 from 34 per cent in 2009-10, according to the Cellular Operators Association of India.
Sector analysts say this might have risen further during 2012-13 to about 55 per cent.
While all the operators have foreign currency loan exposure, Bharti Airtel leads with about 81 per cent (Rs 59,000 crore or Rs 590 billion) of its total debt in forex.
According to Capitaline data, Airtel’s interest outgo is Rs 4,384 crore (Rs 43.84 billion) annually.
Reliance Communications (RCom), which had debt of Rs 37,478 crore (Rs 374.78 billion) till March 31, 2013, had about Rs 27,000 crore (Rs 270 billion) or about 69 per cent, in foreign currency.
About 60 per cent of Idea Cellular’s total debt of Rs 12,263 crore (Rs 122.63 billion) is in foreign currency.
According to a telecom analyst with a management consulting firm, about 80 per cent of the total external debt of telecom companies is dollar-linked.
With the rupee depreciating more than 10 per cent since the start of May, telcos are likely to take a hit.
“Increase in interest payment for foreign currency loans would largely depend on the payment terms.
"If a loan has annual payment mode, there might not be much impact as the rupee value might increase by the time the company needs to pay the annual interest,” said the analyst.
Bharti Airtel’s exposure to the rupee’s depreciation is mainly led by the unhedged $8.7-billion loan the company had taken for its African acquisition.
According to a recent report by Goldman Sachs, a further five per cent decline in the rupee’s value could lower Bharti Airtel’s FY15 estimated earnings per share by 4.1-3.5 per cent.
“Our global debt of around $10 billion is in various currencies and across 20 countries.
"The dollar-rupee movement impacts only the dollar-dominated debt taken in India (about $500 million).
"Our international assets, in Africa for example, are dollar-dominated, with functional currency according to accounting standards being the dollar.
"Accordingly, for any dollar-dominated loan for these, there is no currency fluctuation impact due to the dollar’s appreciation or vice versa,”
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