TV regulator Ofcom has launched an investigation into the ongoing carriage dispute between BSkyB and BT.

BT, which is launching a range of new sports channels this summer, has accused the satellite broadcaster of withholding the supply of Sky Sports 1 and Sky Sports 2 to BT for its YouView service.

Meanwhile, Sky has claimed that BT is refusing to allow Sky to retail the new BT Sport channels wholesale. The channels will still be available to Sky customers, but they will have to contact BT separately to order a subscription.

A BT spokesman said today: "We are pleased Ofcom has decided to open an investigation as we believe Sky has behaved in an unreasonable and discriminatory manner. This is because they have refused to provide Sky Sports 1 and 2 to BT on YouView on fair terms whilst providing them to other pay TV retailers such as TalkTalk.

"While we are continuing to try to resolve this through commercial negotiations, we have asked Ofcom to take urgent action against Sky in the meantime. We are hopeful that Ofcom will deliver an outcome that would be in the best interests of consumers."

Graham McWilliam, Sky's group director of corporate, countered: "In long negotiations with BT, we have tried hard to uphold a simple principle of mutual supply so that both of us would offer all our customers all Premier League matches from next season. However, BT has remained intent on a one-way deal which is loaded in its favour. This is not something that we – or anyone else – could reasonably have been expected to agree to."

The BT portfolio, which includes the channels BT Sport 1, BT Sport 2 and ESPN, launches on August 1 and will feature 38 Premier League games per season.