BT has been accused of failing to invest enough money into the UK’s full-fibre broadband network by the boss of a rival telecoms company.

Rajiv Datta, chief executive of Nexfibre, which is building its own full-fibre network, accused BT of behaving like a “typical monopoly” by failing to invest quickly enough in the next generation of broadband technology.

He said: “When you have somebody that has the dominant market share and has had the benefits of being the incumbent all these years, not investing in that core infrastructure is a typical behaviour of a monopoly.”

BT’s infrastructure arm, Openreach, is spending £15bn to connect 26 million homes to full-fibre broadband.

However, Mr Datta claimed Openreach had only recently begun to accelerate its rollout as a result of competition from start-up rivals such as his business and Cityfibre.

He said: “I think Openreach has seen the impact of that in terms of customers valuing full-fibre and, frankly, moving and transitioning away from that historical, legacy infrastructure.

“There was no incentive for them to invest, there was no real competition. They’re now sensing that there is some competition and that’s gotten them moving.”