The company said the decision was "based on our analysis of the advantages and disadvantages of membership" and said it would now focus its efforts and resources on "Greene King-related lobbying and communications".
However, it stressed that the move "does not signal a desire on our part to reduce our collaboration with other members of the industry where appropriate, far from it".
"In addition to working with other brewers and pub companies on specific initiatives, we plan to adopt an issues-based approach to lobbying, working with policy makers and key influencers to make the case for the pub and pub-goer, the brewer and beer drinker as well as for our own company," Greene King said, in a statement.
A spokesman for the BBPA said: "Greene King has notified the BBPA of its intention to leave in September 2010. We will continue to discuss issues and work with Greene King. We would hope that, in the course of time, it will reconsider its decision."
By Daniel Thomas
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