America's telecoms regulator has unveiled new measures to speed the transition to modern high-speed networks, but critics argue the move could leave behind those in rural areas or with special needs.

The Federal Communications Commission (FCC) says it has adopted rules that let telcos retire their aging copper line infrastructure, and claims this will free up "tens of billions" annually for the rollout of high-speed, all-IP-based networks.

According to the FCC, the build-out of modern networks is hindered by "the need for carriers to divert precious resources to the maintenance of deteriorating legacy networks that deliver outdated services to an ever-decreasing number of subscribers."