BT is considering an appeal against Ofcom, after the communications regulator reduced the prices BT Openreach can charge other operators for access to its network.
Last month, Ofcom said it had notified the European Commission (EC) of the proposed price caps and was awaiting EC approval.
The communications regulator said the prices had to be regulated because BT has significant market power in the delivery of these services.
The move could benefit other operators such as TalkTalk and Sky, as they would pay less to use BT's infrastructure to offer broadband and telephone services to their customers.
In response to the reduced prices, BT has said it would consider an appeal.
"As expected, following last month's draft statement, Ofcom has published the final charge controls for the Openreach LLU [local loop unbundling] and WLR [wholesale line rental] portfolio. These controls, which are reviewed every three years, supersede those previously set by Ofcom.
"We continue to disagree with some of the underlying assumptions they have used to determine these controls, with our primary concern being that we are able to achieve a fair rate of return in order to continue our investment in the future of the UK's communications infrastructure.
"Now that we have received Ofcom's final decision, we will consider all options available to us, including an appeal," BT said.
The EC has made no changes to Ofcom's proposed prices, which sees the annual cost of a fully unbundled line to a property – where an operator takes over the lines to provide broadband and telephone services charged at £87.41 per year – falling from £91.50.
A shared unbundled line to a property, where a communications provider uses a proportion of the line only for the provision of broadband, is currently charged at £14.70 to other operators and will drop to £11.92.
Finally, wholesale line rental, which is used by communication providers to offer telephone services to consumers using lines rented from BT, would drop from £103.68 per year to £93.81 for 2012-13.