Chesterfield Borough Council is being urged by the Leader of Derbyshire County Council not to rush into a devolution deal with South Yorkshire.
Councillor Anne Western is calling for a delay a major decision due to be taken on Thursday 3 March on whether to join Sheffield City Region.
As part of the proposals key services would no longer be provided by Derbyshire County Council.
Desisions over public transport and major planning and investment projects would be handed over to Sheffield City Region if the deal goes ahead.
Cllr Western said: “This will be one of the most significant decisions Chesterfield Borough Council has ever had to make and we think councillors and the public need more than a week to fully understand the implications before a decision can be made.
“It could potentially change the lives of people living in Chesterfield forever. It’s unlikely there will be any sort of public vote for local residents but we think local people deserve to know the facts so they have the opportunity to make their views known.”
Sheffield City Region is a combined authority of councils including Sheffield, Doncaster, Rotherham and Barnsley – controlled by an elected South Yorkshire mayor.