Embarrassing WhatsApps, but no vetting report: what will be in the new release of Mandelson files?

Mandelson, pictured walking his dog last month, is suggested to have given unsolicited advice to ministers on policy areas outside his brief. Photograph: Henry Nicholls/AFP/Getty Images

On Monday the Cabinet Office is expected to publish the second tranche of the Mandelson files – more than 1,000 pages of documents relating to his appointment as UK ambassador to Washington.

The document dump will be the second-largest to the House of Commons after the Chilcot inquiry report into the Iraq war, and its disclosures threaten to again raise awkward questions over Keir Starmer’s judgment in giving Peter Mandelson the UK’s most important diplomatic job.