The advertising regulator is to force The Carphone Warehouse to change its contentious "free broadband forever" campaign.

However, the company will still be able to use the "free" slogan that has so incensed competitors.

The Advertising Standards Authority has received around 150 complaints - many of them from rival internet service providers such as BT and Tiscali - about the way it has aggressively positioned the product as "free".

The broadband service has been advertised as part of its TalkTalk landline offering.

For £9.99 per month, plus £11 line rental cost, customers signing up to its Talk 3 international calls package can receive an 8MB broadband connection.

The "free" marketing tactic has enraged competitors and sparked a broadband price war that could boost the growth of fast internet across the UK.

It is understood that in the upcoming ASA ruling will ban The Carphone Warehouse from using the word "forever" in advertising, because after a period of around six months the broadband offering becomes part of an inclusive package.

And it is understood that it the ASA is determined that the word "free" cannot be used in offering broadband as part of a brand new package - it can only be referred to as "free" if it is offered on top of an existing package at no extra cost.

"[The "free" broadband package] was received less enthusiastically by our competitors who tried to rubbish the offer and complained to the ASA that it was unfair to call it free," said the company's owner Charles Dunstone on his blog (Click here to read it).

"As reported in the press, we have been debating the issue with the ASA over the past few months, their final verdict will be published next Wednesday and we can't reveal its exact contents until then," he added.

"However we are delighted and relieved to be able to report that common sense has prevailed and we will still able to advertise the service as free."

So the firm is to drop the original "free broadband" package launched in April and revert to offering the broadband service as part of its pre-existing £8.99 package - still marketed as "free".

The service has attracted more than 400,000 customers in the months since the ad campaign, which was developed by agency Clemmow Hornby Inge, launched.

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