Sadiq Khan is "gambling with Londoners' safety" for the sake of saving "a very small amount of money".
That is the view of Conservative London Assembly Member (LAM) Tony Devenish, who has slammed the Mayor of London's police merger plans , branding them "reckless".
Mr Devenish is the LAM for West Central, which covers the Hammersmith and Fulham, Kensington and Chelsea, and Westminster boroughs.
Under the new policing plans, announced on Monday (February 12), these three boroughs will come together as one of 12 Basic Command Units (BCUs) in the capital.
More than 300 people have also signed a petition opposing the "tri-borough" BCU merger between Harrow, Brent and Barnet.
The Labour mayor says the move is in response to £325 million of government cutbacks, and the "only way to maintain the frontline services required by Londoners in the face of falling police numbers due to the cuts made by ministers".
The move comes on the back of Mr Khan's decision at the end of last year to close 37 of London's police stations , in a move he also blamed on swingeing government cuts.
But Mr Devenish said different boroughs had different policing needs and priorities.
He said: "The police merger finalised by the mayor is utterly reckless, especially for us here in Kensington and Chelsea.
"The new police merger means that Kensington and Chelsea’s resources will now be shared between Hammersmith, Fulham and Westminster.
"These are neighbouring boroughs, which as you can imagine, have completely different needs and policing capacity to us here in Kensington and Chelsea.
"Westminster, which saw the terrorist attacks last year, has considerably different types of crime, which will see Kensington & Chelsea contend for resources.
"As previous trials of the scheme showed, the merger could mean a slower police response.
"Yes, this scheme will save the force a very small amount of money compared to the Met's total budget, but in pushing to save that cash the mayor is gambling with Londoners’ safety.”
By April, police officer numbers are expected to fall by 2,000 to 30,000, as the larger police command units replace the Met's current 32 borough model.
Announcing his decision, Mr Khan said: "It is a decision that has been driven by cuts from central government to the Met’s budget, and the need to improve policing to meet the demands of London.
"But I want to reassure Londoners that the new units have been designed with their safety as the absolute priority.
"That is why they have been tested since January 2017 and will only be taken forward in a measured way.
"The new units will be designed for every area of London in order to meet the needs of local people and tackle local priorities, while I will continue to press the government to deliver the funding needed to keep Londoners safe.”
Each BCU will be led by one chief superintendent, who will be the BCU Commander.
The roll-out across London will be staggered over the next 12 months following the decision.
The first boroughs to come together will be Ealing, Hillingdon and Hounslow; and Kingston, Merton, Richmond and Wandsworth.
The Mayor of London's office has been approached for further comment.
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