Ofcom has reportedly ordered British phone networks to ban nearly all foreign internet calls pretending to be from UK numbers.
The regulator told the BBC that one operator had already implemented the new plans, while other UK networks are looking for methods to carry this out.
"We've been working with telecoms companies to implement technical solutions, including blocking at source, suspicious international calls that are masked by a UK number," said Lindsey Fussell, Ofcom's networks and communications group director. "We expect these measures to be introduced as a priority, and at pace, to ensure customers are better protected."
The move comes days after the regulator published figures that show nearly 45 million people have been the victim of scam texts or calls in the past three months.
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