Keir Starmer's latest 'fall guy' in the Mandelson scandal signalled he will not go quietly today as allies insisted there was 'no basis' for sacking him.

Foreign Office chief Olly Robbins was ousted last night as the 'furious' PM claimed he was not told vetting officials had warned against appointing the New Labour architect.

Mandelson was installed as US ambassador regardless in February last year.

However, despite Sir Keir saying he was 'unforgivably' kept in the dark, friends of Sir Olly are adamant he did nothing wrong. Ciaran Martin, the former head of the National Cyber Security Centre, said the mandarin would not have been allowed to tell ministers details of the vetting.   

The PM's right-hand man Darren Jones was sent out to make his case in broadcast studios this morning, but appeared to admit that processes had been followed. 

That raises doubts over the grounds for forcing out Sir Olly, a highly experienced civil servant who was on a £240,000 a year salary. Sir Keir told the official he had lost confidence in him following a phone call last night.

The Foreign Affairs Committee has invited Sir Olly to give evidence on Tuesday, in what could be a critical moment for the premier.

There is widespread scepticism in Westminster at the idea nobody in No10 or any ministers knew about the vetting situation until this week. 

Top officials forced out by Sir Keir in the past have already received large severance packages.

They include Chris Wormald, whose exit package was reputed to be worth £260,000 when he was stepped down as Cabinet Secretary in February, barely a year after being installed in the post. 

Mandelson himself received a £75,000 payoff after he was removed as US ambassador over his long-standing ties to paedophile Jeffrey Epstein. Sir Olly himself recommended that settlement.

Sir Keir - who is in Paris for a summit on the Middle East crisis - is facing a rising clamour for his own resignation, with even Labour MPs saying his position is 'not credible'. 

Kemi Badenoch said the PM had 'lied' and was 'taking us for fools'. 'All roads lead to a resignation,' she said. Lib Dem leader Ed Davey said the 'buck stops' in Downing Street.

Sir Keir previously stated that Mandelson passed security vetting, and told the Commons that 'due process' was followed. He learned of the vetting situation on Tuesday, but did not mention the bombshell developments at PMQs the following day.

Facing questions from the media this morning, Sir Keir made clear he had no intention of resigning and seemed to pin the blame squarely on Sir Olly.

'That I wasn't told that Peter Mandelson had failed security vetting when he was appointed is staggering,' he said.

'That I wasn't told that he had failed security vetting when I was telling Parliament that due process had been followed is unforgiveable.

'Not only was I not told, no minister was told, and I'm absolutely furious about that.

'What I intend to do is to go to Parliament on Monday to set out all the relevant facts in true transparency, so Parliament has the full picture.'

Sir Keir has been racking up a startling body count as his Government reels from the Mandelson scandal.

His chief of staff Morgan McSweeney resigned in February saying he took 'full responsibility' for the appointment.

Communications director Tim Allan also left that month insisting he wanted to 'allow a new No10 team to be built'.

At a rally in 2020, Sir Keir promised he would would 'carry the can' for institutional mistakes instead of blaming staff. 

'Hear me out: I had 8,000 staff for five years as the Director of Public Prosecutions… When they made mistakes, I carried the can. I never turn on my staff and you should never turn on your staff,' he told Labour activists. 

He added: 'I will carry the can for mistakes of any organisation I lead.' 

Mr Martin told BBC Radio 4's World at One he was 'disappointed and sad' at the departure of his 'friend' Sir Olly.

'I don't understand what the basis for the dismissal is if I am honest, and I think there's some confusion about the portrayal of what is quite a complicated process of security vetting,' he said.

'The story as I hear it running is that there was a recommendation that Peter Mandelson should fail his vetting, and that was presented as a decision which was then overruled by the permanent secretary - by Sir Oliver Robbins - and that was not communicated to 10 Downing Street.

'All of that story factually in terms of the way the process works is incorrect. I have dealt with lots of security vetting cases in my own career, not least as head of the Cabinet Secretary's office for a number of years...

'It's presented in this story... like a driving test. Somebody assess you, and it's pass fail and then somebody overrules it.

'Particularly at this very senior level that's not the way it works, it is a risk assessment. Most people have some risk attached to them... it could be money, it could be relationships, it could be overseas contacts, it could be relatives or whatever.'

Mr Martin said 'particularly where an appointment has already been announced' the deciding official will be 'presented with an analysis of the risks and a handling plan'.

'The job of, it could be the permanent secretary and in this case obviously it would have been... (is to) say this risk is manageable, therefore we should go ahead, or not,' he added.

'The one thing you never do, is tell ministers, of any kind. Because otherwise the vetting system would collapse.

'If ministers make senior appointments and you go and say look, we've delved into and this is their money, their private life and so forth - then nobody would undertake vetting.'

Mr Martin said Sir Olly had a 'duty not to disclose' vetting details to Downing Street.

'There is no override, it's almost oxymoronic in this case because the decision-taker is the Foreign Office apparatus... And the vetting system is quite explicit that it doesn't tell ministers about the individual details of vetting cases,' he said.

'If the department decides not to give a vetting certificate, then obviously it will become public - it will certainly be made known to ministers that someone has failed their vetting.

'And that is all they would know. They wouldn't be given the details as to why.'

Mr Martin said it was 'for the PM to account for his own words'.

'I simply cannot comprehend the basis of this decision. As far as I can tell from what little we know there is no abuse of process, there's no failure of process, not only is there no duty to disclose the details of a vetting case, there is a duty not to disclose them,' he said.

Mr Martin said there was a 'huge amount' of information publicly available about Mandelson before the appointment.

'It doesn't appear to me that there was anything that he signed of on in terms of this risk assessment that was not already known.

'Therefore I don't see how one could sustain the allegation that he has made a serious misjudgment in this case.'

Mr Martin said he had 'briefly' spoken to Sir Olly. 'I think he is coming to terms with the loss of a job that he loved,' he said.

In his interviews this morning, Mr Jones argued that Sir Keir had been 'right' to tell Parliament that due process had been followed throughout Mandelson's appointment.

He told BBC Breakfast: 'The Prime Minister was right when he told the House that due process had been followed, because it had, but the fact that that process did not require officials to tell the Foreign Secretary or the Prime Minster that they ignored the advice of security and vetting officials is totally unacceptable.'

On ITV's Good Morning Britain programme Mr Jones said the Foreign Office had the 'right' to ignore vetting recommendations.

'As soon as I found out last night that the Foreign Office and a small number of other organisations have the right to ignore the recommendation… I immediately suspended those rights and ordered an urgent audit,' he said. 

Giving evidence to the Foreign Affairs Committee previously, Sir Olly suggested Sir Keir had driven the Mandelson appointment personally. He took over at the Foreign Office after the ambassador announcement was made, but before it was finalised. 

Asked if the Foreign Office would have preferred a different candidate, he said: 'By the time we are describing, it was clear that the Prime Minister wanted to make this appointment himself. 

'Therefore, I understand, the FCDO was informed of his decision and acted on it, and, via the Foreign Secretary, sought and obtained the King's approval for the appointment. 

'In this case, as Chris explained, the Prime Minister took advice and formed a view himself, and we then acted on that view.' 

Nigel Farage has said Sir Olly Robbins is 'one of the most professional civil servants in this country' and 'there is no way' he would have decided to overrule security vetting procedures alone.

The Reform UK leader told LBC: 'There is no way a man like that would unilaterally make a decision of this kind, and, equally, the Prime Minister cannot stand up and say that Mandelson passed security vetting and now claim later he wasn't told.

'That's not incompetence, even Keir Starmer is not that incompetent, it is outright, blatant dishonesty.'