An amendment to the government's Online Safety Bill proposed by MP Sarah Champion on Monday would require telecoms regulator Ofcom to examine whether VPNs are undermining the enforcement of internet regulations.
A VPN is an encrypted connection to the internet that masks a person's location and identity from the websites they are accessing, by routing their data via another computer.
They are commonly used to bypass regional locks on content, by people working remotely who need to access their employer's networks, and by those concerned about their privacy.
But speaking in a Commons debate on Monday Ms Champion said she was worried children could use VPNs to bypass new age verification controls included in the government's bill.
"There are vital protections in the bill, but there is a real threat that the use of virtual private networks — VPNs — could undermine the effectiveness of these measures," the Rotherham MP said.
Ms Champion said evidence suggested that large numbers of teenagers knew how to use a VPN "which means that they can avoid age verification controls".
"So if companies use age assurance tools, as listed in the safety duties of this Bill, there is no guarantee that they will provide the protections that are needed," she said.
"My new clause 54 would require the Secretary of State to publish, within six months of the Bill’s passage, a report on the effect of VPN use on Ofcom’s ability to enforce the requirements under clause 112.
"If VPNs cause significant issues, the Government must identify those issues and find solutions, rather than avoiding difficult problems."
It is likely that all restrictions in the Online Safety Bill can be wholly bypassed by use of a VPN, as the UK government is unable to regulate other countries' connections to the internet – which VPNs give access to.
Virtual Private Networks are widely used by people accessing the internet in countries like China to circumvent government internet restrictions.
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Labour’s frontbench confirmed to The Independent on Tuesday that it was supporting Ms Champion's amendment. Speaking for the opposition in the Commons on Monday afternoon Shadow digital minister Alex Davies-Jones said the unamended bill had "gaps" that needed closing.
"I was pleased to see that my honourable friend the member for Rotherham (Sarah Champion) had tabled new clause 54, which asks the Government to formally consider the impact that the use of virtual private networks will have on Ofcom’s ability to enforce its powers," she said.
"This touches on the issue of future-proofing, which Labour has raised repeatedly in debates on the Bill."
The amendment was not called for a vote on Monday but could return at a later stage depending on the passage of the bill.
Under the Online Safety Bill websites that publish pornography or adult content will have to ask users to prove their age.
Controls could include asking for a credit card or having a third-party service confirm age against government data. Sites that fail to act could be fined 10 per cent of their global turnover by Ofcom.