That would be this Regent's Park Mosque (quoted from Guardian article):
At the Islamic bookstore at Regent's Park Mosque in central London, DVDs of a preacher called Sheikh Yasin are sold. In one DVD, Yasin, who is promoted on the mosque's website, accuses missionaries from the World Health Organisation and Christian groups of putting the 'Aids virus' in the medicine of African people, 'which is a conspiracy'.See also:
Another DVD on sale features Sheikh Feiz, a Saudi-trained preacher. Feiz says: 'Kaffir is the worst word that can ever be written, a sign of infidelity, disbelief, filth, a sign of dirt.'
In a statement the company that runs the bookstore said: 'We sell and supply a wide range of material and we do not necessarily agree with it. It is totally unfair to blame [us] for any of the views expressed in these lectures.'