Takeaways from former top UK official's testimony on Mandelson's appointment

The former leader of Britain's Foreign Office has revealed details about the appointment of Peter Mandelson as the U.K.'s ambassador to Washington despite failing security checks.

Prime Minister Keir Starmer is coming under increasing pressure to resign over Mandelson's appointment.

Starmer has defended his decision, saying he wasn't told about security concerns vetting officials raised about Mandelson.

However, Olly Robbins' testimony Tuesday raises questions about Starmer's judgment.

Robbins says he was pressured to expedite Mandelson's appointment despite incomplete security vetting.

The security concerns were unrelated to Mandelson's ties to convicted sex offender Jeffrey Epstein.