The decision relates to an advert placed by the GPA in the diversity supplement of the Independent in July 2006 which said: "In the last 12 months, the GPA has recorded a 74% increase in homophobic incidents, where the sole or primary motivating factor was the religious belief of the perpetrator."

The advert displayed a pool of blood next to a Bible and attracted fierce complaint from anti-gay Christian groups.

A spokesperson for the GPA told PinkNews.co.uk that ‘‘We are very pleased with the decision today by the Crown Prosecution Service. The GPA never felt any crime had been committed, and certainly never agreed with the complaint that the advert was used to incite hatred.’’

‘‘The GPA were simply trying to highlight their concern over religion being used to justify homophobic hate crime. The GPA believe we have achieved something by the ignition of this very important debate’’.

George Broadhead from the Gay and Lesbian Humanist Association (GALHA) who backed the advert at the time, called the decision a "triumph for common sense."

Gay charity Stonewall's spokesman for public and parliamentary affairs, Alan Wardle, told PinkNews.co.uk: 2It's good that the CPS has recognised that legitimate concerns about faith based homophobia is not a criminal act."

The GPA insisted throughout the case that the advert was never an attack on all faith groups. ‘‘The intention of the advertisement was to cause public debate about an issue that has remained taboo for centuries. An issue that is now having a serious and detrimental effect on the lives of hundreds of law-abiding gay men and women each year and which, on the basis of our records, is growing at such an alarming rate that it could soon become a serious social problem.

“Whilst we accept that such behaviour is not condoned by all sections of all faith groups, neither is it as vehemently denounced as it could and should be. Suspicion exists that there is a lingering distaste for the concept of ‘homosexuality’, indelibly set in the minds of some religious followers.

The protests against the ad were led by Christian Voice whose leader Stephen Green faces trial on Thursday for public order offences after handing out homophobic leaflets at this year's Cardiff gay pride.

When the advert was released it received support from groups such as Outrage!, GALHA and Stonewall for highlighting the increase in homophobic attacks motivated by religious belief.

Peter Tatchell of gay rights group Outrage said: “The advert was simply reporting the facts, it cannot be a crime to expose the truth about hate motivated attacks on gay people’’.

A CPS spokesman told PinkNews.co.uk: "We decided there was no realistic prospect of a conviction in this case."