The kafuffle comes after Sky ran an add claiming its existing subscribers got as good a deal as new customers, unlike Virgin Media subscribers.

"Why do existing Virgin Media customers often pay more than new ones?" Sky's adverts in the UK national and regional press said.

"At Sky we think it's wrong to advertise attractive sounding prices that are often only available to new customers, not loyal ones."

That led five existing Sky customers to complain that, actually, new Sky subscribers often got a better deal than they did.

Complaints included:
* being told it would cost £159 to upgrade to Sky+ compared with £49 for new subscribers
* being told to pay £45 for the Sky+ box and a £40 connection fee, even though new customers only paid for connection
* finding that the offer of a free Sky+ box and free installation only applied to new customers

Sky countered the claims by saying special offers it ran from time-to-time couldn't be compared with its standard prices for subscription and equipment.

"Sky explained that standard prices should be seen as distinct from special offers they ran periodically for time-limited periods," the ASA ruling said.

"They said they did not include their special offers in the comparison claim made in the ad."

But the Advertising Standards Authority (ASA) wasn't impressed that some of Sky's special offers couldn't be claimed by existing customers.

"Because existing Sky customers were not able to take part in some offers, we considered that that contradicted the claim 'we think it's wrong to advertise attractive sounding prices that are often only available to new customers'," its ruling said.

"We were also concerned to note that, whilst Sky did not include their special offers in the comparison, they had included special offers made by Virgin Media to new customers, including some that were time limited."

The ASA found that the ads breached the CAP Code on substantiation, truthfulness, prices and comparisons and told Sky not to run them again.