He added: “Time and time again, opportunities to stop him were missed.
“I am appalled by his crimes and the failures across multiple agencies that could have prevented him from harming, and ultimately killing, more women.”
He said the “multi-agency failings need a multi-agency review” and that lessons should be learned and acted on.
“No woman or girl should be, or feel, unsafe in London,” the mayor added.
In a letter to the director of public prosecution, Nick Timothy, the shadow justice secretary, wrote: “Levy was free to do this partly because your organisation failed to make the case for this sexual predator to be put back behind bars, in spite of warnings from others.”
Former safeguarding minister Jess Phillips told the BBC there had been a “litany of failures”.
“Of course it was Levy who undertook that action, but the state could definitely have prevented it so it has to bear that responsibility,” she told Radio 4.
The Labour MP added that “an idiot could have seen that [Levy was a risk]”.
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