Vodafone Qatar plans to review its costs in an effort to maintain margins, it said after reporting widening losses for a fifth straight quarter on Tuesday.

The telecoms operator has yet to make a quarterly profit, more than six years since ending state-controlled Ooredoo's monopoly in 2009.

The Vodafone affiliate had been moving steadily towards breaking even, but its performance has worsened over the past 18 months as rival Ooredoo has cut prices.

"We shall need to review our cost base further to ensure we sustain our margins," Vodafone Qatar Chairman Sheikh Dr Khalid Bin Thani al-Thani said in a statement to accompany its third-quarter results.

The business made a loss of QR72 million ($19.8 million) in the three months to Dec. 31, against a loss of QR68.9 million in the same period of the previous, according to Reuters calculations.

The result, however, was better than the QR95 million loss forecast by an analyst at Beltone Financial.

Quarterly revenue was QR537 million, down from QR591.5 million a year earlier, which the company blamed on difficult economic conditions and tough competition.

Average mobile revenue per user -- a key industry metric - fell to 110 riyals for the first nine months of the financial year, against QR125 in the same period of 2014.

Vodafone Qatar is 23 per cent owned by parent Vodafone and 22 per cent owned by a government-linked Qatari fund. – Reuters