A council is pulling out of a regional body in charge of improving school standards due to major concerns about how it is run.
Neath Port Talbot council is also unhappy about a quadrupling of its annual contribution to the Education Through Regional Working consortium.
Other concerns include a lack of clarity over how funding is allocated and the poor quality of its reports.
The Welsh Government said anyone stepping away was a "disappointment".
Four regional consortia were set up in 2012 to work on behalf of councils to pool resources and improve school performance.
The ERW also works with schools in Carmarthenshire, Pembrokeshire, Ceredigion, Swansea and Powys.
The proposal to pull out will go to the council's cabinet next week and is due to take effect from March 2020.
If it is rubber-stamped then Neath Port Talbot will be the first council to withdraw from the system.
The authorities said the current arrangements are "clearly failing" in a number of key areas, that it had to "battle to gain access to financial information" and it had been impossible to track funding, "particularly the allocation to schools who need support most".
Schools had voiced "widespread concerns" over the quality of support from ERW, a report by council officials said.
It said head teachers saw only limited value in being part of it and many saw the arrangements a "deadweight and a barrier" to effective school improvement.
The council had previously withheld its contribution to ERW because of concerns about its performance.
ERW's managing director left the role last year and was replaced by a Welsh Government official.
Council leader Rob Jones said it was "most regrettable" that the issues it first raised last year had not been dealt with, leaving it no choice but to pull out.
Neath Port Talbot currently pays £40,000 a year towards ERW but it has been proposed this contribution rises to between £160,000 and £170,000.
The council said it feared an increased risk of redundancy for staff if more funding went to ERW, when it was "trying to get every last penny into our classrooms".
The six council leaders in the ERW region will be meeting with the education minister on Monday.
Ellen ap Gwynn, chairwoman of the ERW joint committee, said: "I'm working closely with partners at the moment to try to resolve some historical long-term challenges".
A Welsh Government spokesman said regional working was "crucial" to raising standards and it was concerned the council feels that ERW has not been managed appropriately.
"We all have a responsibility to work across local authority boundaries, to enable school-to-school co-operation and share best practice on behalf of our young people," he said.
"Anyone choosing to step away and not work in that spirit will be a disappointment to everyone else working hard to maintain and raise education standards across the country."