Vodafone has been shamed for calling its service "the best...bar none".

Rival operator O2 got the hump with two poster ads which stated that Vodafone had the "best call success rate of any mobile GSM network" and was the "Best in Britain bar none".

O2 challenged Vodafone's claim believing that the call success rate on which the claims were based "was not sufficient to justify the general superiority claim for mobile network performance".

The Advertising Standards Authority (ASA) upheld the complaint saying that Vodafone could not make such a "general superiority claim over the other mobile networks". ®