BT has been squeezed by rivals in the cut-throat battle for broadband customers as it reported the lowest level of customer growth for two years.

The telecoms giant, which has invested heavily in TV football rights in its battle with Sky, reported net retail broadband additions of 88,000 in the second quarter to the end of September.

It said the figure was lower than in recent quarters "due to strong promotional activity in the market".

The results suggested rivals Sky and TalkTalk were fighting back after BT's £738 million deal to air 38 Premier League games a season appeared to be paying off.

The TV sports package is offered for free to customers taking its internet and telephone services. BT has also paid £897m to show Champions League football from 2015.

The group said it had enjoyed a successful start to its second season of showing top-flight football with ­audiences up 45 per cent on average with a peak of 1.25 million watching the opening league fixture between Manchester United and Swansea.

BT said it added 38,000 customers for its own TV platform in the quarter and also announced a partnership with Netflix allowing BT customers to sign up directly for the video streaming service.

Revenue from the group's consumer arm rose seven per cent to £1.06 billion for the quarter, including a 17 per cent rise in turnover from broadband and TV.

BT's adjusted pre-tax ­profits were up 13 per cent to £690 million for the quarter and were 10 per cent ahead to £1.33 billion for the half-year.