Government action sought over nuisance call 'number spoofing'
A watchdog has called for tougher action against so-called nuisance call number spoofing, warning that their increasing use was undermining the UK's caller ID system.
Which? said some call centres were using software to "spoof" the caller ID system into hiding their real identity.
Householders could instead see a fake number with a local area code, or any number a call centre considered looked trustworthy enough, and be tricked into picking up the phone, the consumer group warned.
It said the deception had become a "major problem", with Ofcom estimating that as many as two billion nuisance calls were made each year using spoofed numbers.
And it warned that such calls were undermining the caller ID system, which had become a trusted barrier to nuisance interruptions in UK households over the last two decades.
Which? said it wanted to see the caller ID system made more secure and companies legally obliged to present a valid number when they made outbound marketing calls.
Which? executive director Richard Lloyd said: "Number spoofing is yet another twist on the modern day menace of nuisance calls.
"At best this practice is frustrating for people who are already sick and tired of getting nuisance calls, and at worst it could lead to you being the victim of fraud.
"We want the Government to keep its promises on making firms give an accurate number when making outbound marketing calls.
"We also need senior executives to be held personally accountable if their company makes unlawful sales calls."
Under Ofcom rules, companies are not obliged to give caller ID details, but if they do they must present numbers accurately or face a fine of up to £2 million.
To date, no companies have been charged with this offence as number spoofers are often based overseas and difficult to identify.
Which? noted that not every company that altered its caller identification did so for malicious purposes, and could display a freephone 0800 number to allow customers to call back without charge.