Evening summary

• Peter Mandelson failed his security vetting clearance but the decision was overruled by the Foreign Office to ensure he could take up his post as ambassador to the US, an investigation by the Guardian can reveal.

• The Conservatives, Reform UK and the Greens have all said that Keir Starmer should resign in the light of the Guardian revelations because he misled MPs, or lied to the public, about the Mandelson appointment. The Liberal Democrats have also said that Starmer should quit if it is established that he has lied. Starmer will find it hard to argue that he was being honest when he said at a press conference in February that Mandelson got “clearance” from the vetting process (see 4.35pm, 4.43pm and 5.11pm) if people do not believe he only found out about the vetting this week. (See next point.) But he may find it easier to justify his vague comment in the Commons about “due process” being followed, because the process does allow vetting decisions to be overruled (see 4.35pm).

• No. 10 released a statement that said Starmer was not aware that Mandelson had failed the security vetting until this week. That is likely to raise further questions about who knew – and also why Starmer was not informed.

• The SNP will cap supermarket prices for essential goods such as bread and milk if it retains power, John Swinney has pledged, after describing the cost of living as “the defining issue of this election”.

For a full list of all the stories covered on the blog today, do scroll through the list of key event headlines near the top of the blog.

Stephen Flynn, the SNP’s Westminster leader, has written to the independent adviser on ministerial standards, Laurie Magnus, to demand that he investigate whether Keir Starmer misled the public over Peter Mandelson.

In a statement Flynn accused Starmer of “making contradictory claims about the process followed when appointing him to the highest diplomatic office in these isles.”

He added:

Today Keir Starmer has been caught in what appears to be nothing less than a shocking lie – he claimed Peter Mandelson passed security vetting when we now know the very opposite to be true. These new revelations are the most serious yet for the Prime Minister.

No 10 said that Starmer was only made aware that Mandelson failed his vetting this week (see 6.09pm).

Kemi Badenoch laid out her position more clearly in a pool interview with a member of the press.

She said:

There are three serious concerns here. The first is that on the 10th of September, the prime minister misled parliament by saying that full due process was followed. If Mandelson failed the security vetting, full process was not followed. Misleading Parliament is a resigning offence.

On the 5th February, at a press conference in Hastings, the prime minister said that Peter Mandelson cleared the vetting process. This is not true. That means he broke the ministerial code by saying something deliberately untrue. Starmer has misled the country.

And the third thing is that it looks like there’s been a cover-up, because we had a Humble Address in parliament where we asked for all of the documents. This did not come out then. It’s gone to the press. That means that something was being covered up. On each of these three things, we have a resigning offence for the prime minister. This is a very serious situation.

When pressed on the implications for Starmer’s position, she said: “If he has misled Parliament, as it looks like he has, he should resign. If he has broken the ministerial code, as it looks like he has, he should resign.

“If he withheld documents by a cover-up from parliament, he should resign. I’m only holding him to the same standards to which he’s held previous Prime Ministers - that if they mislead parliament, they should resign. This is the standard which he sets himself.”

Badenoch here is referring to Starmer’s conversations with Boris Johnson. Starmer previously said Johnson should step down as prime minister if he broke the ministerial code by misleading parliament.

Downing Street has just issued a statement saying Starmer did not know that Mandelson had failed the vetting process until earlier this week. A No 10 spokesperson said:

The security vetting process for Peter Mandelson was sponsored by the FCDO. The decision to grant Developed Vetting to Peter Mandelson against the recommendation of UK Security Vetting was taken by officials in the FCDO.

Neither the prime minister, nor any government minister, was aware that Peter Mandelson was granted Developed Vetting against the advice of UK Security Vetting until earlier this week.

Once the prime minister was informed he immediately instructed officials to establish the facts about why the Developed Vetting was granted, in order to enact plans to update the House of Commons.

The government is committed to complying with the humble address in full as soon as possible. Any documentation within the scope of the humble address that requires redaction on the basis of national security or international relations will be provided to the ISC. This will include documents provided to the FCDO by UK Security Vetting.

This is from Aubrey Allegretti at the Times.

A Labour MP texts: “We were at the beginning of the end a while back. This is the end of the end.”

We have got a panel by Paul Lewis, Henry Dyer and Pippa Crerar with five questions outstanding from this controversy.

Steven Swinford, the Times’s political editor, has got even more. He has posted these on social media.

If the official line ends up being that Keir Starmer didn’t know, his private office didn’t know, that Number 10 didn’t know, that the Cabinet Office didn’t know, it poses so many questions

Taking that claim at face value for a moment:

1) Why did Starmer assert ***categorically*** that Mandelson had cleared security vetting when he hadn’t?

2) Why did Starmer and No 10 repeatedly, over a period of many months, say that ‘due process’ had been followed when it hadn’t?

3) Why did the Foreign Office not inform the prime minister that Mandelson had failed his vetting?

4) Is it really credible that the foreign office decided to take this decision in some kind of hermetic bubble - a decision of huge consequence, with direct ramifications for the prime minister? It seems insane

5) In February, when humble address was tabled including the request for all information about Mandelson’s vetting, did nobody think to check that Mandelson had indeed passed his vetting?

6) Why were documents about Mandelson’s security vetting withheld from the first tranche of the Mandelson files? They were specifically requested in the humble address and yet they are absent. The Guardian reports that there is a debate in government about whether they will be published?

The broader question for the prime minister is whether **not knowing** that Mandelson had failed his vetting was enough of an excuse for giving categoric public assurances that he had cleared vetting in public

Emily Thornberry’s statement this evening (see 5.33pm) implies that Olly Robbins, who as head of the Foreign Office is most likely to have been the person who agreed that Peter Mandelson’s appointment as ambassador could go ahead despite his failing the vetting process, may be the figure being set up to get the blame for all this.

Jason Groves, the Daily Mail’s political editor, thinks this may be Keir Starmer’s best survival strategy.

Claiming ignorance - and blaming Foreign Office/Olly Robbins - is probably the only possible way to counter claims Starmer deliberately lied to Parliament about Mandelson (immediate resignation territory). But good luck getting anyone to believe it...

According to the BBC, Peter Mandelson is letting it be known that he was not aware that he had failed the security vetting ahead of his appointment as ambassador to the US.

Pippa Crerar is the Guardian’s political editor.

At the end of last year Sir Olly Robbins, the head of the Foreign Office, gave evidence to the Commons foreign affairs committee about the vetting process ahead of Peter Mandelson as ambassador.

The committee now intends to summon Robbins for a follow-up hearing.

Emily Thornberry, the Labour MP who chairs the committee, told the Guardian:

Looking at the evidence that was given and the letters that have been written, to be charitable, there are glaring holes. It really is a question of whether we were knowingly misled.

Nigel Farage, the Reform UK leader, says that Keir Starmer “blatantly lied” at his press conference on 5 February (see 5.11pm) and should resign.

Keir Starmer said in February that the security services had given Mandelson “clearance for the role”.

Now we discover that he has blatantly lied, the Prime Minister should resign.

Vote Reform on May 7th to make it happen.

This is from Pippa Crerar, the Guardian’s political editor.

Friends of Morgan McSweeney told the Guardian that he had no knowledge of Peter Mandelson’s developed vetting process or the outcome.

Here is the full quote from what Keir Starmer said during a Q&A with journalists on 5 February this year when asked about the Peter Mandelson scandal. At that event, in Hastings, Starmer clearly said that Mandelson had passed security vetting.

According to this report in the National, Starmer said:

There was a due diligence exercise that culminated in questions being asked because I wanted to know the answer to certain issues.

That’s why those questions were asked. The answer to those questions were not truthful.

There was then, I should add, security vetting carried out independently by the security services, which is an intensive exercise that gave him clearance for the role, and you have to go through that before you take up the post.

Clearly, both the due diligence and the security vetting need to be looked at again.

I’ve already strengthened the due process. I think we need to look at the security vetting, because it now transpires that what was being said was not true.

UPDATE: Here is the video clip.

Prospect, the union which represents civil servants working at UK Security Vetting (UKSV), says No 10 was wrong to allow people to think that vetting was not carried out properly.

In a statement, the union’s general secretary, Mike Clancy, said:

It is deeply unfortunate that following the resignation of Morgan McSweeney Downing Street allowed the impression to circulate that the vetting of Peter Mandelson had not been done correctly by UK Security Vetting.

Not only were UKSV put in an invidious position by being asking to conduct vetting after an appointment had been announced, but now deeply troubling reports have appeared in the media claiming that UKSV advice was overruled.

Civil Servants, particularly those working in the most sensitive parts of government cannot speak publicly, and deserve ministers to take responsibility for the decisions they take and not to seek to deflect blame onto them.

The Green party is also calling for Keir Starmer’s resignation over what he said about Peter Mandelson’s appointment as ambassador to the US – and what he subsequently said about.

The party issued a statement from the Green MP Siân Berry saying:

Keir Starmer has lied and lied again over his decision to appoint Peter Mandelson and he must resign. Starmer told parliament ‘due process’ had been followed. This report makes clear that was untrue.

He has tried to blame the vetting process, when in fact it is reported that a decision was taken to ignore a failed vetting. We need answers on what and when Starmer and David Lammy knew about this decision to overrule the vetting report.

The precise reasons for Mandelson’s failure to pass this vetting must be made public, even though it was known to everyone that Mandelson was friends with the world’s most notorious paedophile prior to the appointment. It is outrageous that it is being reported that senior government officials are now considering whether to withhold from parliament documents that show Mandelson wasn’t given security clearance.

No more buck passing, no more mysteriously vanishing mobile phones, the public need the truth.

Ed Davey, the Lib Dem leader, also suggesting that this could be a resignation matter for Keir Starmer. He has posted this on social media.

If Keir Starmer has misled Parliament and lied to the British people, he has to go.

Although this is quite similar to what Kemi Badenoch is saying (see 4.06pm), she is saying Starmer did mislead MPs, while Davey is still treating that as unresolved (“if”). As explained earlier, on the basis of what we know, the misleading parliament charge is contestable. (See 4.35pm.)

But Davey says lying to the public (ie, at a press conference) should also be a resignation matter, and on this Starmer is on more shaky ground. (See 4.35pm.)

UPDATE: Davey has also issued a slightly longer version of the social media post. He says:

Keir Starmer had already made a catastrophic error of judgment. Now it looks as though he has also misled parliament and lied to the British public. If that is the case, he must go.

Labour came into Government on a promise to clean up politics. Instead we’re seeing the same old sleaze, scandal and cover-ups as we did under the Conservatives