The European Commission has said that BT should offer competing providers physical access to its underground ducts and overhead poles "as soon as possible " in order to deliver superfast broadband connections to the whole of the UK without delay.
The EC agrees with Ofcom that BT should continue to provide competitors with virtual access to its optical fibre infrastructure for the time being, but argued that this should not be a permanent solution.
Physical access should be provided to other providers as soon as it is " technically and economically possible", said the EC.
"In this specific instance, virtual unbundling seems the best option to safeguard competition and enable consumers to benefit from a wider range of services provided over next-generation fibre infrastructure," said EC Digital Agenda Commissioner Neelie Kroes.
"However, this interim solution is not a long-term alternative to physical fibre unbundling, which should be imposed as soon as possible."
Virtual unbundling gives all telecoms firms a virtual connection to the BT network, but physical unbundling would allow BT competitors to deploy their own fibre networks.
The benefit of the latter approach, according to the EC, is that it is likely to encourage communication providers to rollout fibre networks faster than BT.
The latest Ofcom statistics show that 46 per cent of Britons have access to superfast broadband connections, and a central pledge in all the political parties' manifestos before the general election was to expand access to the rest of the population as fast as possible.
The Conservative Party said that it would do this by opening up access to BT's ducts.
BT is already providing other communication providers with virtual access to its fibre networks via its Openreach services. Ofcom and the EC have endorsed Openreach, but maintain that it needs to be enhanced to provide physical access to BT's fibre networks.
Physically unbundling fibre networks may mean that BT has to share information with its competitors about its available fibre capacity and the quality of its ducts.
"Our view is that the current Virtual Unbundled Local Access product meets the needs of the industry, but we will obviously work closely with Ofcom going forward," said BT today in response to the EC statement.
The local loop in the UK, which delivers traditional broadband via copper telephone lines, was physically unbundled from BT years ago.
Operators have been able to upgrade individual lines using DSL technology to offer services such as always-on high speed internet access direct to the customer.
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