Simon Case, one of Sir Keir Starmer’s most senior government officials, has announced he will step down at the end of the year on health grounds.
The Cabinet Secretary told the Prime Minister he is to leave Downing Street on doctors’ advice 18 months after he was diagnosed with a neurological condition.
He left with a warning to his colleagues that they must avoid being dragged into party politics and remain impartial servants of the Government, rather than partial participants in it.
Mr Case, who has been a senior aide to the last six prime ministers, privately told Sir Keir before the election that he would be leaving this year, The Telegraph understands, and formally confirmed it on Monday morning.
In his letter to colleagues, he made it clear the timing of his departure is nothing to do with reports that he had been accused of failing to get a grip on leaks about “freebies” from Lord Alli and about rows over the role of Sue Gray, Sir Keir’s chief of staff.
He told them: “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.”
He added: “Whilst the spirit remains willing, the body is not.”
In the valedictory letter to colleagues, Mr Case, who is also the head of the Civil Service, urged them to embrace reform and warned them not to act in a partisan way, as officials have often been accused of doing in the past.
It comes after reports that Ms Gray would like to replace Mr Case with Oliver Robbins, the former Brexit negotiator, or someone else aligned with the Prime Minister’s political stance.
Mr Case wrote: “We should resist the temptation to become the arbiters of, or participants in, legitimate democratic debate, leaving party politics to politicians and demonstrating our enduring and profound belief in democracy through the service of the elected government of the day.”
He also said: “The world is changing fast and so must the Civil Service. The global context, the relentless evolution of technology, increasing public expectations of the services they consume and many more factors require us to keep adapting.
“At the same time, the core values of our United Kingdom have not changed and so I hope that the Civil Service will hold onto its fundamental purpose and values in the never-ending task of serving the Government of the day and, through them, the people of our country.”
The Prime Minister will appoint a new cabinet secretary following what Mr Case emphasised would be “a full, open and transparent process” in which an independent panel chaired by the First Civil Service Commissioner will conduct interviews and advise Sir Keir on suitable candidates for the role.
Concentrating on treatment
Mr Case, 45, was appointed to his current role by Boris Johnson in 2020 to help steer the country through the Covid crisis. He remained in place under Liz Truss, Rishi Sunak and Sir Keir.
He had previously worked as principal private secretary to Lord Cameron and Baroness May during their premierships, before a two-year spell as private secretary to the Prince of Wales.
Mr Case has told friends that his neurological condition, which affects his eyesight and causes him to walk with the aid of a stick, means he can no longer commit to what is in essence a seven-day-a-week job beyond the end of the year.
A father of three, he has not lived full time with his family for the past 14 years because of the need to be available 24 hours a day, and he has told friends he is looking forward to living at home full time and concentrating on treatment for his condition.
He said he eventually hopes to do some charity work to raise money for research into his condition and wants to write some papers on the constitution, but will not be writing a memoir.
He told colleagues: “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.”