Ofcom has delayed by up to "a week to ten days" the publication of an "urgent" investigation into allegations that BT's new phone tariffs are anti-competitive.

In March, the UK's dominant fixed-line telco announced plans to scrap its "standard rate" in a move it said would simplify its tariff structure and make its service even better value for money for its customers.

Rivals pointed out that scrapping the standard rate line rental would increase the cost of competing services run by companies such as The Carphone Warehouse, Telse2 and Tesco*.

As a result, the UK's communications regulator - Ofcom - began an investigation at the end of March and said it would make an initial ruling within four weeks.

That self-imposed deadline has now passed.

A spokesman for Ofcom said that publication of this initial ruling had been delayed because of the "volume of data" officials are sifting through as part of the investigation.

Ofcom's ruling is expected in the "next week to ten days", said the spokesman. ®

* Yesterday, Tesco mobile announced it has signed up 250,000 new customers since its launch in September 2003. The supermarket chain, which also offers fixed-line and mobile telecoms services, said it had beaten its initial sales target and was "well on track to ensuring its place as a significant player in the UK mobile market".

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