Prime Minister Keir Starmer is facing a parliamentary vote on whether he should be subject to a formal inquiry over claims related to the vetting process for Peter Mandelson's appointment as ambassador to the United States.

Commons Speaker Lindsay Hoyle has granted a debate on the matter, allowing MPs to vote on whether the Prime Minister should face a parliamentary probe. The Conservative Party requested the vote, which has prompted strong reactions from Downing Street.

Number 10 has dismissed the proposed vote as "a desperate political stunt by the Conservative Party," rejecting the need for any formal investigation into the appointment process. The government appears to be mobilizing support to defeat the motion, with reports suggesting former Prime Minister Gordon Brown has been enlisted to help persuade MPs to vote against the probe.

The controversy centers on questions about the vetting procedures surrounding Mandelson's nomination to the key diplomatic post in Washington. The debate represents a significant parliamentary challenge for Starmer's government, forcing MPs to take a formal position on the matter.

The timing of the vote adds political pressure on the Prime Minister, who must now manage both the immediate parliamentary challenge and broader questions about government appointment processes. The outcome will depend on how many MPs from different parties choose to support or oppose the inquiry motion.