No 10 keen to kickstart search for cabinet secretary’s successor

Downing Street is pushing to launch the formal search for a new cabinet secretary within the next month amid frustration with Simon Case, who is yet to officially announce his departure.

Case has acknowledged he intends to leave in the new year due to health reasons, but the lack of a formal announcement means No 10 has not been able to kickstart the hunt for a successor. One Downing Street source said the government would like to begin the process imminently.

The cabinet secretary, who was appointed under Boris Johnson, has long been expected to move on given the election of a Labour government.

However, he has remained in the top job during Starmer’s transition to power. The prime minister’s chief of staff, Sue Gray, has historically had an uneasy relationship with Case, who did not give her a permanent secretary job when she was a senior civil servant and oversaw an investigation into her departure to work for Labour .

Since Labour came to power, some within Downing Street also blame Case or those close to him for briefings about tensions between the camps of Gray and Morgan McSweeney , Starmer’s head of political strategy. A Cabinet Office spokesperson denied that Case was behind any briefing, saying: “This claim is categorically untrue.”

Case is likely to want to step down on his own terms, having made clear in early discussions with Starmer before the new government that he would leave his cabinet secretary job for health reasons in the new year. He took a medical leave of absence late last year, returning in January.

He will have to agree a departure date with the prime minister, and it would be expected that the recruitment of a new cabinet secretary would take a number of months, with the Civil Service Commission also involved.

When Case does go, there are several high-profile names in the frame for a job , including Oliver Robbins, the former chief Brexit negotiator, and Sharon White, the departing chair of the John Lewis Partnership.

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From within the civil service, Antonia Romeo, the permanent secretary of the Ministry of Justice, and Jeremy Pocklington, the permanent secretary of the Department for Energy and Net Zero, are seen as leading contenders.

However, No 10 sources said they wanted an open and wide competition to get the best possible candidate. There has never been a cabinet secretary who was not a white man.

Robbins has long been thought the favourite for the job, but some Whitehall sources believe he is instead being lined up as national security adviser.

The Guardian revealed last month that Starmer had cancelled the appointment of one of Britain’s top generals as the national security adviser.

The prime minister has overturned the decision made in April by his predecessor, Rishi Sunak, to appoint Gwyn Jenkins, then the vice-chief of the armed forces, to the most senior security position in the government, officials have said.

Although Jenkins will be allowed to apply again for the job, some in Whitehall believe Starmer’s decision is another sign of his determination to promote allies to the most important roles in the civil service.

One official said: “This looks like another part of the grab for power by Keir Starmer and [his chief of staff] Sue Gray. The process to appoint Jenkins was run with full transparency, and there is no good reason to do it all over again.”