BTinternet found itself on the wrong side of the Advertising Standards Authority yesterday for describing BTinternet Anytime, its unmetered dialup internet package, as 'reliable', despite complaints from people that they couldn't use the service.

The ASA received objections about the service from frustrated users who could not access it despite the promises on a banner advertisement on BT's website that read, "BTinternet Anytime for a fast, reliable service".

According to a special report on BBC's Watchdog programme last week, users heard an engaged tone almost every time they tried to connect to their accounts. Some even accused BT of attempting to boost subscriptions to its more reliable broadband package BTopenworld. These allegations have not been proved.

BT said the problem was not the fault of the ISP but was due to busy telephone exchanges. The ASA dismissed this and said the adverts were still misleading.

"Because intermittent and ongoing problems were preventing customers from connecting to the internet, the ASA considered that the advertiser's claim that their service was reliable was misleading," said the ASA statement.

Contrary evidence produced by BT that showed results from customer surveys indicating customers were happy with the unmetered package was also dismissed.

BT has removed all banner ads until the issue has been resolved.