Keir Starmer 'WAS told about Lord Mandelson's red flags - then waved them away'

But it has now been claimed that Sir Keir was already aware of his "red flags" ahead of the security protocol - then went ahead with his appointment anyway.

The UK Security Vetting agency (UKSV) recommended the rejection due to Lord Mandelson's ties to China and Russia, insiders said.

But the advice was later overruled by former Foreign Office chief Sir Olly Robbins, after he determined that the security risk presented was manageable.

Sir Olly was axed from his role on Thursday after losing the confidence of both the Prime Minister and Foreign Secretary Yvette Cooper after the bombshell new details came to light.

Sir Keir said it was "staggering" he was not informed of Lord Mandelson's failure of the process.

The Government claimed last week that the Prime Minister would have pulled the appointment if he had been made aware of the rejection.

“The reality is that Starmer had already been warned about the major risks and he had waved them away," one senior Whitehall source told The Telegraph.

Sir Olly claimed he was unable to inform the Prime Minister due to the Constitutional Reform and Governance Act of 2010 - a claim ministers have rejected.

A No10 statement on Sunday night said that although civil servants rather than ministers make decisions on vetting and clearance, there was nothing in the law to prevent ministers being told.

Downing Street has insisted there was no reason he could not have "sensibly" told the Prime Minister.

On Tuesday, Sir Olly will appear before the Foreign Affairs Select Committee, where he is expected to outline his reasonings for withholding the information from Sir Keir.

The former Foreign Office chief is also expected to argue that he overruled the UKSV's recommendation as the concerns surrounding Lord Mandelson's appointment had already been "priced in".

Last month, he told MPs it was apparent “the Prime Minister wanted to make this appointment himself”.

Sir Keir is also facing mounting pressure over the revelations that the ex-Labour peer was handed the highest level of security clearance during his spell in Washington despite his vetting failure, The Times reported last night.

Lord Mandelson was granted "strap three" during his tenure - reserved for information that would pose a major security risk in itself or to Britain's intelligence services.

It is shared on a "need to know basis" and is likely to include sensitive information surrounding Russia and China - to which Lord Mandelson's ties presented a red flag during the vetting process.

He was warned it could take "at least three months" for strap clearance to be approved - but was fast-tracked due to the significance of the ambassadorial role, according to the newspaper.

Ahead of his Commons grilling today, Sir Keir told the Mirror he would make it "crystal clear" to MPs that he had been kept in the dark.

The Prime Minister said: "The fact that I wasn’t told that Peter Mandelson had failed his security vetting when he was appointed is astonishing.

"The fact that I wasn’t told when I said to Parliament that due process had been followed is unforgivable, and that’s why I intend to set out in Parliament on Monday the facts behind that, so there’s full transparency in relation to it.

“Am I furious that I wasn’t told? Yes, I am. Am I furious that other ministers weren’t told? Yes, I am. I should have been told, and I wasn’t told.”

In a scathing letter to the PM on Sunday, Tory leader Kemi Badenoch wrote: “As an experienced barrister you will know the importance of telling the truth, but you will also know that many people think you have been at best recklessly negligent and at worst dishonest about this whole affair.

“You have failed to answer very simple questions about what you did and what you knew.

“This is contemptuous of Parliament, discourteous to the House, and against the fundamental requirement set out in your own Ministerial Code.”

Lord Mandelson was sacked last year, just nine months into his DC posting, after further details of his association with the paedophile financier Jeffrey Epstein emerged.

Mrs Badenoch said: “This has been a tawdry and shaming affair for you and your party, and for this country.

“Not only have you damaged our relationship with the United States and insulted the victims of the paedophile Jeffrey Epstein, but you have also undermined our national security by giving the highest diplomatic post to an individual that the security services found to be of ‘high concern’.”

GB News has approached No10 for comment.

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