TORY Cabinet minister Gavin Williamson is under official investigation after allegedly sending “threatening” messages to his party’s former chief whip, according to reports.

Wendy Morton, who served as Conservative chief whip under Liz Truss, is said to have submitted screenshots of “vile and threatening” messages sent over weeks to the party headquarters.

A friend of Williamson, a former education secretary who was awarded a controversial knighthood by Boris Johnson, told Tortoise he “strongly refutes these allegations”.

Williamson, who has twice been sacked from Cabinet, was given the role of minister without portfolio at the Cabinet Office by Rishi Sunak when he took power in October.

READ MORE: Rishi Sunak asked if Scotland is 'hostage in British colony'

The new Prime Minister had his judgment called into question after reappointing Suella Braverman as Home Secretary just days after she was forced to quit over breaching the ministerial code.

The fresh allegations against Williamson have sparked similar concerns. 

Angela Rayner, Labour's deputy leader, said: "These new revelations raise fresh questions about Rishi Sunak’s woeful judgment in resurrecting ministers who left Government under a cloud of misconduct.

"Gavin Williamson was sacked from Cabinet twice, yet despite risking national security he has now been put at the heart of the Government's corporate headquarters.

"Given his new role and the seriousness of these allegations, there must be an urgent and independent investigation.

"Far from restoring integrity, professionalism, and accountability, Rishi Sunak is failing to stop the rot. He promised that appointing an independent ethics adviser would be one of the first things he would do as Prime Minister, but instead he has given us more of the same old sleaze."

Security concerns were raised about Williamson's reappointment as he was sacked as defence secretary in 2019 following an inquiry into a leak from the National Security Council.

During Sunak's first PMQs, he was asked by Labour MP Stephen Kinnock if he had sought or received "any advice on security concerns about [Williamson] before his appointment to the Government yesterday, given that he was sacked in 2019 for leaking sensitive information relating to our national security?”

Sunak avoided answering the question, saying only that the incident "happened four years ago".