Copeland MP Trudy Harrison has arranged an urgent meeting at Whitehaven Academy after it was announced popular headteacher Warren Turner is stepping down.
The "appalled" MP called for a thorough investigation into the decision, which was revealed by Bright Tribe Trust this morning (Friday).
In a letter to staff, the trust said: "Warren Turner has come to the realisation that now is the time for him to move on to another role."
Mr Turner has been praised by the school community for his leadership during a difficult time.
Bright Tribe is expected to leave the academy at the start of next month, with Cumbria Education Trust, which has been responsible for the day-to-day running of the school since September, taking over.
In a press release from Bright Tribe, Mr Turner said: “I have relished my role as headteacher of the Whitehaven Academy over the last two years.
"I’ve been very lucky here in that the whole community - from pupils and teachers through to parents and politicians - have been the most supportive and inspirational groups I have ever encountered in my career so far.
"I’ve been humbled by the community buy-in to my approach and grateful to them for giving me a chance. It would be an understatement to say that my tenure as head has not been without its challenges.
"However, I am justifiably proud of all we have achieved together in providing a successful platform for the future.
"Although I will be extremely sorry to leave the academy, I have come to the realisation that now is the right time for me to move on to another role with similar levels of challenge either in school improvement or headship."
Angela Barry, interim chief executive at Bright Tribe Trust, sponsor of the academy, said: “Warren has provided strong leadership during a time of turbulence and uncertainty putting the local community at the heart of the school’s journey to become the local school of choice.”
But Mrs Harrison said: "I'm absolutely shocked, I have just found out from the Chair of the Academy Management Committee, George Beveridge, this morning (Friday).
"I've had no communication from Cumbria Education Trust or Bright Tribe despite me asking questions over the last few weeks about where Warren is.
"He had a period of sickness at the start of term and when he returned I wrote a letter welcoming him back.
"I was later made aware he had been advised to take time off while the terms and conditions of his employment were agreed.
"I can't believe this. There should be a thorough investigation to be sure an all too common non-disclosure agreement has not been used.
"I know Warren Turner is a man of integrity. I have made a promise to stand behind him and Whitehaven Academy.
"I've arranged an urgent meeting at 2.30pm at the academy to get to the bottom of this."
The MP also plans to hold a public meeting next week to discuss the issue. Date, time and venue to be confirmed.
Andrea Bateson will step up from senior assistant headteacher to interim head of school within the academy in Cumbria while a process starts to appoint a permanent replacement.
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