The Advertising Standards Authority (ASA) has accused internet service provider (ISP) NTL of potentially misleading consumers by advertising its 128Kbps service as broadband without qualifying the speed.

Its decision follows a complaint by rival ISP Freeserve and a member of the public who objected to NTL's technical definition of broadband in a national advert.

The advert stated that NTL offered 'High Speed Broadband Internet only £14.99 a month' referring to its 128Kbps service.

It was suggested by the complainants that their understanding of broadband services were those with a speed of 500Kbps and above.

The ASA acknowledged NTL's defence of the wording, which adhered to Oftel's and the Department of Trade and Industry's (DTI's) definition of broadband as "higher bandwidth always-on services offering data rates of 128Kbps and above".

But the ad watchdog insisted that consumers could be confused. It stated that most of the public "would understand broadband to mean a service of upwards of 500Kbps [and] that the claim 'broadband', without qualification, was likely to mislead".

The ASA also asked the ISP to include a prominent reference to the speed of the service in its adverts.

NTL has agreed to remove the 'high speed' claim, but told vnunet.com that it was "very disappointed" with the ruling.

"This is not an issue about what is broadband. But now when we write adverts, we've got to think of what the ASA thinks people will think about broadband," said a spokesman.

"This has got to be wrong when we have followed the definitions laid down by the experts including Oftel and the DTI."

Freeserve welcomed the ruling. "There's a great deal of confusion about what is meant by broadband," it said.

"At Freeserve we believe it is 500Kbps and above, and it's about time Oftel and the government cleared up the uncertainty."