That trio of questions was put to Mandelson in an email from Sir Keir’s chief of staff McSweeney on his behalf.

The peer, I’m told, replied to those questions in an email in which Downing Street sources now say he was “economical with the truth”.

It’s understood Mandelson believes that he was truthful and frank about his association with Epstein, and told No 10 that he had not stayed in Epstein’s Manhattan apartment in 2009 while Epstein was in prison. Another source confirmed that he told Downing Street he had not stayed there.

Court documents revealed in 2023 Epstein told his private banker that Mandelson would be staying at the property. Mandelson has never explicitly denied or confirmed he did, although it has been reported that he had no recollection of doing so.

It’s worth noting that none of those issues – the possible house stay, the charity, or the continued friendship – were discovered during the vetting process. They had been reported in previous years.

But the guarantees relayed to the prime minister by Mandelson were considered sufficient to be worth the gamble of giving him the job.

Once the appointment was then made, sources suggest the “developed vetting” process then kicked in, under the auspices of the Foreign Office.

The normal process for government appointments is dependent on the job being given and the sensitivity of the material and information to be handled.

But there is scarcely a job with a higher level of trust required than the White House ambassador, given the two countries’ links on security, defence, trade and intelligence.

I’m told nothing was flagged to No 10 as a result of the DV process, which would have involved an in-person interview which in this case, “ought to have been completely forensic, but they must have used the wrong lens,” according to another senior figure.

Unlike the PET file, Downing Street would not receive the results of such a process as a matter of course, even in an extremely high-profile appointment. The DV process is a standalone routine.

And Downing Street sources insist that they weren’t made aware of any problems, so everything went ahead.