Keir Starmer has taken full responsibility in Peter Mandelson’s appointment as UK ambassador to the US.

In his first comments since the government released a tranche of documents related to the former Labour peer’s appointment, the prime minister told reporters: “I made a mistake in appointing Peter Mandelson.

“Let me follow that up with – as I’ve done before, but I need to do it again – but an apology for the victims of Epstein.

“It was my mistake and I take responsibility in relation to it.”

The documents were released amid ongoing questions about why the government appointed Mandelson even though his friendship with the paedophile Jeffrey Epstein was public knowledge.

Starmer has since insisted that Mandelson, who was sacked in September, lied to him about the depth of that relationship.

The government files show the prime minister was warned of the “reputational risk” which could accompany giving Mandelson the role.

The rest of the files – including further questions put to the ex-ambassador about Epstein by No.10 – are yet to be released.

Scotland Yard asked the government to hold back some information to avoid prejudicing their probe into misconduct in public office allegations against Mandelson.

Starmer told reporters: “The release of the information shows what was known, that led to further questions being asked.

“Unfortunately because of the Metropolitan Police we can’t release that information yet but that doesn’t take away from the fact that it was me who made the mistake, and it was me who makes an apology to the victims – and I must do that.”

The No.10′s spokesperson also told reporters that, while “due process was followed” in appointing Mandelson, it’s clear that vetting and security is not up to scratch.

They added: “The prime minister did read the advice but clearly there are lessons to be learnt on the wider processes.”

Starmer’s representative rejected accusations from Tory leader Kemi Badenoch of a “cover-up” within the documents.

Some of the pages include boxes for the PM to respond to his official advice over Mandelson’s appointment but they were left blank.

The spokesperson said: “I refute the suggestion of a cover-up. The government’s complied fully. I just don’t accept that it’s the case at all.

“There are a range of different ways in which the prime minister’s senior team responds to advice.”