Mandelson scandal is biggest crisis for diplomatic service in decades, says ex-Foreign Office chief

Simon McDonald was the permanent under-secretary of the Foreign Office until 2020. Illustration: Simon McDonald/The Guardian

The Peter Mandelson security vetting scandal is the biggest crisis for the diplomatic service in decades, a former Foreign Office chief has said.

Simon McDonald, who was the permanent under-secretary of the government department until 2020, has spoken out in defence of Oliver Robbins, saying the civil servant was “thrown under a bus” by the prime minister, Keir Starmer, when he was dismissed from his role on Thursday.