BT is to upgrade a further 2.5 million premises in the UK to support its copper-based broadband service that offers 'up to' 20Mbps.

The Telecommunications company says that by spring 2013, 90 percent of the UK will be able to access the service, which is an increase on its original target of some 20 million premises, or around 80 percent of the country.

Some 800 exchanges will be upgraded to enable this roll-out, with half of them being located in rural areas that serve around 90,000 premises in total.

"This is a significant expansion of our roll-out plan and is further proof of our commitment to serve rural areas. The faster speeds will support the government's aim of enhancing broadband speeds for both town and countryside," said Alex Pannell, director of product management at BT Wholesale.

President of the Country Land and Business Association (CLA) William Worsley said BT's announcement would provide "economic power" to rural Britain.

"The necessary copper upgrade of exchanges to provide access of at least 2Mbps will give economic power to rural areas. However, we are still concerned that at least 10 percent of rural areas may never have access to fixed line broadband and this is where the government's promised funding for rural broadband should be targeted," he said.

"Too many areas across the UK have very limited access to mobile telephony. Extending better mobile phone coverage to rural areas is as important as ensuring effective broadband for businesses to compete fairly with their urban counterparts and to prevent communities from being socially disadvantaged."

BT's announcement comes just a week after BT was forced by Ofcom to drop the price it charges ISPs to use its network to offer broadband in rural areas, in a bid to improve services in these areas.