Lisa Chambers has today resigned from Suffolk County Council.
The Newmarket and Red Lodge councillor made the decision to quit after 10 years with the authority.
Mrs Chambers has been on the county council’s cabinet for eight years and was serving as the cabinet member for education and skills.
In a statement Cllr Colin Noble, leader of Suffolk County Council, wished his former colleague well for the future.
He said: “I would like to thank Lisa for her hard work and dedication in her role as cabinet member for education and skills.
“I am sure that Lisa would agree with me that the most important thing is the education and welfare of children across Suffolk.
“The work we are doing through Raising the Bar to improve educational attainment will continue at pace. This work is already delivering across the system and I am confident that improvement will continue. Our commitment to 100% of schools being good or outstanding remains a priority.
“In the interim, Gordon Jones, cabinet member for children’s services, has agreed to pick up the additional responsibilities for education and skills.
“I wish Lisa well for the future.”
Mrs Chambers is understood to have told all her colleagues she was stepping down because she was finding it impossible to work as a cabinet member and member of the Conservative group.
She said that the removal of some of her local Newmarket work by Cllr Noble had been a step too far.
Following the former deputy council leader’s resignation, a by-election will be held in Newmarket and Red Lodge.
Mrs Chambers was contacted by the Bury Free Press but declined to comment.