British mobile phone giant Vodafone logged an annual net loss of 6.3 billion euros ($6.9 billion) on Tuesday after slashing the value of its troubled Indian division.

The performance in the 12 months to March compared with a net loss of 5.4 billion euros in the previous financial year, it said in a statement.

Revenues declined 4.4 percent to 47.6 billion euros.

At the same time, however, operating profit excluding exceptional items almost tripled to 3.7 billion euros on the back of a painful cost-cutting drive.

In the first half, Vodafone initially took a non-cash impairment of 5 billion euros on its Indian activities and blamed a sharp increase in competition.

However in March, Vodafone announced the merger of its Indian unit with Idea Cellular in order to create India's largest telecoms operator and fight ultra-competitive new player Reliance Jio.

Following the deal, Vodafone added it had partially reversed the Indian impairment, but it still stood at 3.7 billion euros over the year.