The head of the civil service Simon Case has announced he will resign at the end of the year on health grounds.
The Cabinet Secretary, 45, said in a letter to colleagues that he has been undergoing medical treatment for a neurological condition over the last 18 months.
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He wrote: “Whilst the spirit remains willing, the body is not.
“It is a shame that I feel I have to spell this out, but my decision is solely to do with my health and nothing to do with anything else.”
Mr Case returned to work in January after two months off sick, though this is the first time he has publicly confirmed his condition.
He was appointed Cabinet Secretary in September 2020 by then Prime Minister Boris Johnson, making him the UK’s most senior civil servant.
He has hit the headlines throughout his role, most recently regarding reports of tensions at the heart of Number 10 between Mr Case and Sir Keir Starmer’s chief of staff Sue Gray.
Mr Case also featured heavily during the COVID inquiry, when messages revealed he was often exasperated by the Johnson administration, describing the former leader’s inner circle as “basically feral” and suggesting his wife Carrie was “the real person in charge”.
In his letter to colleagues, Mr Case gave a nod to the turbulent years in which he has served in the top job, saying: “It has been an honour to serve two sovereigns, four prime ministers and over 120 Cabinet ministers in this role.”
“There have been far more ups than downs along the way and by far the greatest highlight has been the privilege of working with so many remarkable public servants, across the length and breadth of our country, in our overseas posts and with counterparts from our close allies and partners around the world.”
A recruitment process for the next cabinet secretary has begun.
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