The analysis, which was commissioned by the West Midlands Mayor, was handed over to councils in March but has not yet been made public.
It is expected to claim that Black Country authorities have failed to utilise all available former industrial land for development in the controversial Black Country Plan (BCP).
The councils insist they have exhausted possible brownfield options, meaning some green belt development is inevitable.
More than 7,700 homes have been lined up for the region's green belt in the BCP, sparking a wave of protests by campaigners bidding to protect sites including The Triangle in Kingswinford and Calderfields West next to Walsall Arboretum.
Mr Street said: "We must all work together to help protect the precious and irreplaceable green belt land around the Black Country, and I am confident the report will help achieve this and support the Black Country Local Plan to progress.
"The study has now been passed over to the Black Country local authorities as evidence to help inform their local plan work, and it is for them to choose when to publish alongside other evidence.
"I hope to see it made available for the public as soon as possible."
Bobbi Owen, from Walsall's Save Our Green Belt campaign group, said: "Taxpayers' money has been used to fund this report. It should be made available immediately for those taxpayers to read."
Dudley Council leader Patrick Harley said that while he wants the report published, he doubted there would be many brownfield sites missed off the BCP that were suitable for development.
"I know there's one in there, the old gas works in Gornal, that our officers have already rejected for a variety of reasons," he said.
"Some of these old industrial areas can look ideal for development but when you scratch below the surface it is just not feasible."
He added the council remained determined to remove as much of Dudley's green belt as possible from the plan, having already taken out two sites.
"There's clearly a strength of public feeling," he said. "If you look at The Triangle there's 10,000 signatures on a petition against it. You just can't ignore that."
The four councils have written to Housing Secretary Michael Gove suggesting the region's housing targets are too high.