Multimillion-pound plans by three police forces to outsource services to the firm at the centre of the Olympics security debacle have collapsed.
But their newly-appointed commissioners have decided to drop the plans - while still making clear that they would consider working with other companies.
Doubts had been raised about the plans after G4S was forced to admit serious failings in its Olympics contract last summer, which led to more police and soldiers being called in.
Hertfordshire police and crime commissioner David Lloyd said: "I have always said that I would make my decision once the evidence was received and assessed.
"It is now clear that the G4S framework contract through Lincolnshire Police was not suitable for the unique position of the three forces."
However, he confirmed he was already in talks with other companies and would keep open the prospect of working with G4S in Hertfordshire.
"I still believe that substantial elements of policing support services will be best delivered by the private sector and will ensure that this option is immediately pursued," he said.
Police and crime commissioner for Bedfordshire, Olly Martins, said he was "pleased" with the joint decision but added: "We do still have to save money.
"Strengthening the ways in which we collaborate with Hertfordshire and Cambridgeshire is a crucial element of our on-going investment in all our police services," he said.
Kim Challis, chief executive of G4S Government and outsourcing solutions, said its "compelling proposition" would have guaranteed savings of £100m over 10 years.
"Our proposition was to operate back office services at the volume and scale required to deliver significant savings to forces, enabling them to concentrate their resources on frontline roles: it was never about replacing police officers," he said.
"This has already proved to be the case in Lincolnshire, where we have a successful partnership which, in less than a year, has seen us deliver savings in running costs of around 16%.
"We continue to work with a number of signatory forces on the Lincolnshire Police contract, including Hertfordshire, to see how we can help them to generate the savings they need."
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