Suffolk County Council’s ruling Conservative group was in turmoil today following the shock resignation of education spokeswoman Lisa Chambers.

She resigned from the authority following disagreements with leader Colin Noble – and within hours former leader Mark Bee launched a savage attack on the new leader.

Mr Bee sent a tweet saying: “I’m sorry to see Lisa resign. It illustrates yet again that Colin Noble is not fit to lead SCC or hold the Cons(ervative) Group together.”

The former leader and his political friends believe that Mr Noble worked behind the scenes to undermine his leadership after mounting an unsuccessful bid for the top job in the Tory group in 2014.

Mr Bee decided not to re-stand for the group leadership in April’s election but his preferred candidate Jenny Antill was defeated by Mr Noble.

Mrs Chambers resigned from the council just hours after representing the authority at a headteachers’ conference at the Center Parcs in Elveden.

She quit after Mr Noble removed her from her position as county council representative and chair of the steering group of the Newmarket Vision – which is in her home division.

She lives in Red Lodge and expressed her unhappiness about the decision in a letter she sent to fellow councillors marking her departure.

She said: “Over the recent months I have felt that it has become impossible for me to continue as a member of Cabinet and within the Conservative Group.

“There are many things happening at a local and national level that I do not agree with, the final straw came for me when the Leader decided to remove my local Newmarket work from me – a local councillor without their local role was a step too far for me, this role was removed without consultation or explanation.”

Mrs Chambers insisted, however, that her decision to resign had nothing to do with the council’s education policy which has come under fire over recent years.

And she said she was confident the changes that had been introduced would show improving results in future years.

Mrs Chambers said: “I always said that changing education was like turning a supertanker – it would take time. We have turned around the supertanker and it is now heading in the right direction.”

She said she felt it was the right time to do something else with her life: “I felt I should make a clean break so I have resigned from the council as well as the cabinet. But I shall still be living here and playing my part in the community.”

Mrs Chambers said she had always intended to stand down from the county council at the next election in 2017

“I have had a wonderful time in terms of the roles I have been given. But I think it is time to move on and do something new.”

She did not want to comment on the contents of her letter to fellow councillors.

In the wake of the resignation, Mr Noble issued a statement saying: “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.”

In response to Mr Bee’s attack Mr Noble said: “I do not respond to personally abusive tweets. Mark clearly has not moved on (from the leadership election) and we very much want Mark to be a fully active part of the group.

“We would like him to come back to our awaydays and take a full part in making the decisions of the group.”