Revenue also fell, by 1.8 per cent to 4.977 billion pounds in the three months to September 30, compared with the equivalent period in 2009, BT added in an earnings statement.
Pre-tax profit however rose 13 per cent to 496 million pounds, beating analyst expectations and prompting BT chief executive Ian Livingston to raise the group's forecast for underlying earnings.
"We have made significant progress in improving profitability and cash flow, enabling us to invest in building the foundations for revenue growth in 2012/13," he said in the statement.
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