It was a prescient and – as it turned out – incredibly optimistic sign off from Peter Mandelson after eight years as Chancellor of Manchester Metropolitan University.

“I hope I survive in my next job for at least half that period”, the Financial Times reported him as saying – with a smile.

As something of a serial sackee from government posts, we know Sir Keir Starmer was, to an extent, aware of the risks of appointing the ‘Prince of Darkness’ as his man in Washington.

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But in his first interview since he gave the ambassador his marching orders, the prime minister said if he had “known then what I know now” then he would not have given him the job.

For many Labour MPs, this will do little to answer questions about the slips in political judgement that led Downing Street down this disastrous alleyway.

Like the rest of the world, Sir Keir Starmer did know of Lord Mandelson’s friendship with the paedophile Jeffrey Epstein when he sent him to Washington.

The business secretary spelt out the reasoning for that over the weekend saying that the government judged it “worth the risk”.

This is somewhat problematic.

As you now have a government which – after being elected on the promise to restore high standards – appears to be admitting that previous indiscretions can be overlooked if the cause is important enough.

Package that up with other scandals that have resulted in departures – Louise Haigh, Tulip Siddiq, Angela Rayner – and you start to get a stink that becomes hard to shift.

But more than that, the events of the last week again demonstrate an apparent lack of ability in government to see round corners and deal with crises before they start knocking lumps out of the Prime Minister.

Remember, for many the cardinal sin here was not necessarily the original appointment of Mandelson (while eyebrows were raised at the time, there was nowhere near the scale of outrage we’ve had in the last week with many career diplomats even agreeing the with logic of the choice) but the fact that Sir Keir walked into PMQs and gave the ambassador his full throated backing when it was becoming clear to many around Westminster that he simply wouldn’t be able to stay in post.

The explanation from Downing Street is essentially that a process was playing out, and you shouldn’t sack an ambassador based on a media enquiry alone.

But good process doesn’t always align with good politics.

Something this barrister-turned-politician may now be finding out the hard way.

Sir Keir Starmer will be “completely exonerated” over the scandal around Peter Mandelson’s relationship with disgraced financier Jeffrey Epstein, Gordon Brown has told Sky News.

The prime minister was forced to sack Lord Mandelson as the UK’s ambassador to the US last Thursday after details of the peer’s relationship with Epstein emerged in the media.

Emails between Lord Mandelson, a minister under Tony Blair and Mr Brown, and the convicted sex offender revealed that the ex-minister sent messages of support to Epstein even as the US financier faced jail for soliciting prostitution from a minor in 2008.

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Sir Keir said on Monday that he would have “never appointed” Lord Mandelson as US ambassador if he knew then what he knows now.

But Mr Brown told Sky News’ Darren McCaffrey that he believes the prime minister will be “completely exonerated” once “the record is out” on the matter.

The former prime minister said: “I don’t want to criticise Sir Keir Starmer’s judgement, because he faces very difficult decisions and we’re talking about a very narrow area for timing between a Tuesday and Thursday.

“I think once the record is out, Sir Keir Starmer will be completely exonerated.”

However, Mr Brown did admit that the situation “calls somewhat into his judgement”.

He said: “I think every government goes through difficulties. Probably 15 years ago, when I was in government, you’d be asking me questions about what had happened on a particular day.

“But this is not really in the end about personalities. In the end, it’s about the policies.

“If you ask people in the street, they might say, well, interesting story, terrible thing that happened to these girls, but also they will say, look what’s happening to my life at the moment, what’s happening to my community, what’s happening to my industry, what’s happening to the whole region.

“I think we’ve got to think that politics is about changing people’s lives and making a difference in those areas where they want to do things.”

Sir Keir has insisted that Lord Mandelson went through a proper due diligence process before his appointment.

However, speaking publicly for the first time since he sacked Lord Mandelson on Thursday night, he said: “Had I known then what I know now, I’d have never appointed him.”

Sir Keir said he knew before Prime Minister’s Questions on Wednesday afternoon that Lord Mandelson had not yet answered questions from government officials, but was unaware of the contents of the messages that led to his sacking.

He said Lord Mandelson did not provide answers until “very late” on Wednesday, which was when he decided he had to be “removed”.

A top Downing Street aide has resigned after sending sexually explicit messages about independent MP Diane Abbott, Sky News understands.

Paul Ovenden, who was the director of strategy at Number 10, is understood to have left the role on Monday after a number of instant messages from 2017 became public.

Sky News understands he did so to avoid becoming a “distraction” for Sir Keir Starmer, just days after he was forced to sack the UK’s ambassador to the US – Peter Mandelson – over his ties to disgraced financier Jeffrey Epstein.

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The messages, exchanged between Mr Ovenden and a female colleague, contained the graphic retelling of a conversation he reportedly overheard about Ms Abbott while at a party.

The former aide has alleged these were not his original words, but said he “deeply regrets” sharing them.

He said: “I really, deeply regret my sharing this story, and the hurt and embarrassment its publication will cause.

“Accordingly, I have brought forward my resignation to today as I do not want to be a distraction from the government’s work.”

It is understood Mr Ovenden announced to colleagues before the summer recess he was leaving his role, and had planned to leave “quietly and quickly” sometime this month.

However, in the wake of the publication of these messages, Mr Ovenden “brought forward” his resignation to today.

The messages, exchanged with a female colleague and seen by Sky News, described a game of “shag, marry, kill” the aide overheard while at a party in May 2017.

This involved explicit descriptions about suspended Labour MP Ms Abbott.

A Number 10 spokesperson said: “These messages are appalling and unacceptable.

“As the first black woman to be elected to parliament, Diane Abbott is a trailblazer who has faced horrendous abuse throughout her political career.

“These kinds of comments have no place in our politics.”

Sky News has contacted Ms Abbott for comment.

The latest Number 10 resignation comes as Sir Keir admitted he never would have appointed Lord Mandelson to the post of UK ambassador to the US if he had known what he knows now about the extent of his association with Epstein.

Speaking publicly for the first time since he sacked Mandelson last Thursday, the prime minister explained that a “due diligence process” was conducted before he was appointed to the post in February.

“I knew of his association with Epstein,” Sir Keir said.

“But had I known then what I know now, I’d have never appointed him.”

Just days before Lord Mandelson was sacked, Angela Rayner resigned as deputy prime minister and housing secretary after admitting she did not pay enough tax on her second home.

She also quit as deputy leader of the Labour Party, an elected post.

Sir Keir’s second-in-command admitted to Sky News political editor Beth Rigby on the Electoral Dysfunction podcast that she should have paid the higher rate of stamp duty on a home she bought in Hove, East Sussex, as it was her second property.