Peter Mandelson assured ministers that the Government would “never regret” appointing him as UK ambassador to the US, newly released documents show.

The second tranche of the so-called Mandelson files contain hundreds of private WhatsApp and email exchanges between Lord Mandelson, current and former Cabinet ministers, senior civil servants and special advisers.

They include texts between Mandelson – who was sacked last September over his links to convicted sex offender Jeffrey Epstein – and current welfare minister Pat McFadden, who said the Prime Minister had “destroyed” his own authority by watering down his benefit reforms last year.

Shorts

Also included is a handwritten note from Mandelson to then-foreign secretary David Lammy, who was told the Government would “never regret” appointing him as ambassador.