British Telecoms regulator Oftel says it has ordered BT Group to cut charges for wholesale unmetered Internet access by 17 per cent.
Oftel said the decision came after an investigation which concluded BT, the country's dominant fixed-line phone company, had been charging operators for certain call routing and call management measures that were no longer necessary.
The regulator had previously proposed cutting the charges in April, when it said savings from any price cuts could be passed on by the other operators to their Internet service provider customers - who include Freeserve and AOL.
The investigation was opened following a complaint from Cable & Wireless Plc, one of BT's telecoms rivals.
Oftel said that whereas BT once used one of its own types of networks to manage dial-up traffic, improvements in late 2001 meant the company no longer had to use this network.
But BT still included charges for using that network in its wholesale dial-up pricing, regardless of whether wholesale buyers such as Cable & Wireless needed that level of service.