The civil service probe into whether senior officials said Jeremy Corbyn would not be “physically or mentally” up to the job of prime minister will have an independent element, Labour has said.
The comments follow a 45-minute meeting between the head of the civil service Sir Mark Sedwill, the Labour leader, and the party’s shadow Cabinet Office minister Jon Trickett – which was described as “frank”.
The meeting came in the wake of demands by Mr Corbyn for a fully independent probe into the matter.
A Labour Party spokesperson said: “The meeting was frank and detailed, with a full exchange of views.
“The seriousness of the civil service breach and the evident malicious intent behind it was acknowledged by all participants in the meeting.
“Jeremy Corbyn and Jon Trickett pressed the case for a fully independent investigation to restore trust and confidence in the civil service.
“They were promised an independent element to the civil service investigation, that they will receive regular updates on its progress and that it would report as soon as possible.
“They made clear the credibility of the investigation will be assessed on the basis of its results.”
Before the meeting, which took place in the Labour leader’s Westminster office, Mr Corbyn’s spokesman said the actions by the unnamed officials at the “apex of the Civil Service” were “out of order”.
The row was triggered by a report in The Times, which said the future of Mr Corbyn, 70, was openly discussed at an event attended by mandarins amid suggestions he has become “too frail and is losing his memory”.
One civil servant was quoted as saying “there must be senior people in the party who know that he is not functioning on all cylinders”, while another said “there is a real worry that the Labour leader isn’t up to the job physically or mentally but is being propped up by those around him”.
Mr Corbyn’s spokesman said what happened was “entirely unacceptable” and “unprecedented in recent times”.
It was also based on false information because Mr Corbyn is in “excellent” health, the spokesman added.
He said: “You have clear evidence in reports of senior civil servants briefing against the elected leader of the Opposition and not only briefing against him and claiming he is not up to the job but also briefing on the basis of false information – namely that he is ill or his health is impaired.
“That is entirely untrue so on both counts you are talking about a very serious breach of Civil Service neutrality, a principle that absolutely underlines our democratic constitution.”
It is not appropriate for the Civil Service “to be marking their own homework” and there should be an “independent element in the investigation to restore confidence in those people at the apex of the Civil Service”, he said.
The spokesman suggested the briefing against Mr Corbyn could be linked to Establishment anxiety about the prospect of a radical Labour government.
“Clearly there is resistance and anxiety in sections of the Establishment about the election of a radical, transformative Labour government that is determined to redistribute wealth and power,” he said.
“That clearly is the context in which this is taking place.”
Downing Street insisted a Civil Service investigation is the correct way to proceed.
“The Civil Service is responsible for looking into any potential breaches of the Civil Service Code and this is no different,” the Prime Minister’s official spokesman said.
“If we are able to identify any individual responsible we will take appropriate disciplinary action.”