India’s biggest mobile operator Bharti Airtel disappointed with a drop in profit for the quarter to 31 December 2011, although the company did report solid growth in its African units.

According to Bloomberg, customers of Airtel’s core Indian operation have cut phone usage, following a tariff increase that came after a fierce price war in the country. The operator’s average revenue per mobile user in the country decreased to INR187 (US$3.80) in the quarter from INR199 in the prior-year period.

Airtel noted that its profit was impacted by higher tax provisions, while also citing the impact of 3G licence fee amortisation and increased interest costs.

For the quarter to 31 December 2011, there was a group-level net profit of INR10.1 billion (US$200 million), down 22.4 percent year-on-year, on revenue of INR184.8 billion, up 17.1 percent. According to the Wall Street Journal, analysts were expecting profit of INR13.6 billion on revenue of INR184.5 billion.

Airtel saw double-digit revenue growth in both its India & South Asia operations and in its Africa businesses. Revenue from its India & South Asia mobile services for the period was INR101.8 billion, up 11.1 percent year-on-year. Revenue from Africa was US$1.1 billion, up 16 percent.

In total, the company has a little under 233 million mobile subscribers, up 17 percent year-on-year. The bulk of these, 182 million, are in India & South Asia, which saw a 16 percent growth, with just under 51 million in Africa, which grew by 21 percent.

The quarter saw the first positive operating cash flow for its Africa businesses. The company also passed the 50 million customer milestone in this region.