A £140,000 atheist campaign on buses stating ''There's Probably No God'' is not in breach of the advertising code in spite of more than 300 complaints, a watchdog ruled today.

The Advertising Standards Authority (ASA) said it had concluded that the campaign, which is running on buses in Southampton, did not contravene the code and it would therefore not launch an investigation - the case is now closed, it said.

The authority said it had received 326 complaints about the campaign, some claiming it was offensive to people of faith and others challenging whether the advertisement was misleading.

''The ASA Council concluded that the ad was an expression of the advertiser's opinion and that the claims in it were not capable of objective substantiation,'' a statement said.

''Although the ASA acknowledges that the content of the ad would be at odds with the beliefs of many, it concluded that it was unlikely to mislead or to cause serious or widespread offence.''

The campaign, with the slogan ''There's probably no God. Now stop worrying and enjoy your life'' was launched earlier this month following a fundraising drive supported by the British Humanist Association.