The Mayor of London Boris Johnson said: "London is home to almost half of all people living with HIV in the UK, but a quarter of them are unaware they carry the virus.
"It is vital that people who might be at risk get tested, not only to reduce the risk of transmission to others, but to ensure they get the life-saving treatments that are available."
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The Mayor of London said action was needed to "mitigate and palliate" the effects of the cuts on lowest income families.
The mayoral candidate said he believed the spike in knife crime and the restrictions imposed on police to stop and search are linked.
Dragos Moisica raped the victim on her 12th birthday in a hotel in Kenton. He has been jailed for 12 years.