A legal battle is on the cards over a Devon city breaking away from the rest of the county when it comes to handling its own affairs.
Exeter says the move will save money in the long run
Devon County Council has voted to legally challenge the decision to give Exeter City Council unitary status.
The city council got the go-ahead by the government to become independent of the county council in 2009.
Exeter would take on education, libraries and social care in the independence move.
However the county council's executive committee has decided it is going to mount a legal challenge, arguing it has strong enough grounds for a judicial review.
Exeter City Council says it will cost £6m to become a unitary authority, but that it could then save £12m a year on administration costs.
But Local Government Minister John Healey said when he announced unitary status for local authorities there were affordability "risks" in Exeter's proposal.
He said Exeter was one of four councils which would have to submit further information on the "financial viability" of their proposals before being totally signed off in September.