A former senior police officer believes plans to merge the Barking and Dagenham force with those in two neighbouring boroughs is down to funding and “nothing to do with greater productivity”.

David Gilbertson, a former deputy assistant commissioner at Scotland Yard, says former colleagues have spoken to him about leaked plans for the pilot scheme which will see it Barking and Dagenham join with Redbridge and Havering later next month.

Mr Gilbertson, who retired from the Metropolitan Police in 2001, claims the need to find a further £800m in savings by 2020, in addition to the £600 million already being withdrawn from Met’s funding is behind the move.

He said: “The real reason for the amalgamation of the London Boroughs of Redbridge, Barking and Dagenham, and Havering is funding.

“It has absolutely nothing to do with greater productivity.”

The former officer believes the pilot proposes a reduction in management level officers and criminal investigation detectives across the three boroughs based at a central hub.

The Met Police responded to the claims by stating elements will be “streamlined”.

A spokesman said: “The trial will deliver a saving of two borough commanders, further work is underway to establish the correct ratio of supervisors and managers to officers, the trial will test the concept once we have agreed a ratio. The trial will look to streamline processes and we are testing the concept of whether we can deliver this with reduced management.”

A spokesman refuted claims response cars handling 999 calls will not have a Havering-based hub.

The Met’s latest response to changes believed to be occurring in the coming years has been described as “laughable” by Mr Robertson. “The Met needs to be honest about the reasons for these changes, and how success or failure of the project will be measured. They need to be open about what is planned, which will affect over 750,000 people who live and work in outer east London,” he said.

While the Met insist there are no plans to sell any police stations in Hornchurch and Rainham in the pilot, questions remain over their long-term existence in the coming years.