About one million premises catered for by Virgin Media's cable broadband network have been overbuilt by projects supported by Broadband Delivery UK (BDUK), new research has found.
This is the finding of ISPreview.co.uk, which believes the number of premises affected is between 950,000 and 1.1 million.
The government's £1.6 billion BDUK scheme was launched five years ago with the aim of making speeds of 24Mbps available to 95 per cent of the UK by December 2017.
In August this year, it confirmed that 4.55 million homes and businesses now have access to a superfast broadband service thanks to the initiative, meaning it is on course to hit its primary target by the end of this year.
However, ISPreview.co.uk points out that this figure does not account for the overbuild of Virgin Media, as they are not able to use the public subsidy.
A spokesperson for BDUK commented: "Only infrastructure that is required to target non-superfast premises is eligible for subsidy. If there is overspill to other premises then these are not eligible for subsidy, and they are not counted towards the contractual superfast delivery targets.
"However, these premises are included in the gainshare calculation, so we benefit from any additional take-up resulting from them."
Virgin Media has already raised concerns about the use of state aid in the past. Speaking to ISPreview.co.uk three years ago, Virgin Media Head of Public Affairs Daniel Butler said there is no need or value to the taxpayer in using public funds to build networks "where they already exist".
BDUK's longer-term aim is to reach 97 per cent of UK premises by 2020.