Currently rival companies to BT can access the former monopoly’s telegraph poles and underground ducts to lay their own fibre networks to reach residential and small-business customers.

Under the new plan, BT will have to extend this approach to rivals serving large businesses as well, improving the business case for other telecom firms to focus on fibre.

Ofcom’s competition group director Jonathan Oxley said: “Our measures are designed to support the UK’s digital future by providing investment certainty for continued competitive investment in fibre and 5G networks.”  

“The amount of internet data used by people in the UK is expanding by around half every year. So, we’ll need faster, more reliable connections for our homes, offices and mobile networks.”

Ofcom said it plans to consult in December on proposals for a review of business telecoms market rules for the five years from 2021.

An Openreach spokesperson said the division shares Ofcom’s desire to improve industry service. “Our ducts and poles have been open to other companies since 2011, and we recognise that unrestricted access is a natural next step, so we had volunteered to get on with that, ahead of Ofcom’s original schedule”, it said.