The album, 'Get Rich Or Die Tryin'', is out on Universal Music's Interscope label and is the soundtrack to a film of the same name which will be released on January 20.
On the poster, 50 Cent is shown from the back with a gun tucked into his belt and holding a baby. The image was taken from promotional material for the film, in which he plays a character whose story is based on his own life as a drug dealer turned rap star.
Universal said that the image was intended to show the choice that 50 Cent had to make between the child and the violence represented by the gun.
The ASA ruled that the image was irresponsible and likely to cause serious or widespread offence. It said that 50 Cent's association with gang culture and criminal behaviour, combined with his credibility with young people, was likely to be seen as glamorising the possession and use of guns.
It also considered that the combination of the title 'Get Rich Or Die Tryin'' and the image could give the impression that success could be achieved through violence.
The ban follows the withdrawal of 'Get Rich Or Die Tryin'' film posters in the US cities of Los Angeles and Philadlephia by billboard company Clear Channel in November in reponse to complaints.
There was also a storm in the UK last April over 50 Cent's role in Reebok's 'I Am What I Am' campaign. A TV ad showing the rapper counting to nine – referring to the number of times he was shot at in a planned hit in 2000 – was pulled by Reebok after 55 complaints.
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