When cabinet ministers’ special advisers received an email ordering them to attend a meeting with Dominic Cummings at 7:55am on Monday, some feared the worst.

Boris Johnson’s chief aide has moved to aggressively attempt to tackle the culture of leaking, disloyalty and laziness that he believes existed among government advisers during Theresa May’s premiership.

The “crackdown” — as it is being described by Number 10 officials — has left Whitehall aides in two minds. Several departmental advisers, known in Westminster as SpAds, welcomed the change, telling BuzzFeed News it was badly needed and had provided the government with energy and purpose. Others said it had instilled an atmosphere of fear and division that was sapping morale. Some worried that they could lose their jobs at any moment.

Many suspect Cummings has also sought to send a message to the EU via briefings to Whitehall aides that Johnson is serious in his determination to pursue a no deal Brexit if a new deal cannot be reached by October 31, and that Parliament cannot stop him from doing so. Some believe he is employing a Nixonian “madman strategy”: attempting to convince Brussels the new prime minister is hellbent on leaving at any cost, in the hope of securing a better deal.

One aide described Cummings’ no-nonsense interventions over the past two weeks as a “jihad on SpAds”. In an indication of how pervasive the language of violence is in Westminster, they were actually using the phrase as an endorsement of the new regime.

At Monday morning’s meeting, Cummings told the assembled aides that they were to produce a list of tasks for their departments to prepare for no deal, that it was time for them to “interrogate” their ministers and officials and raise any Brexit planning issues with Number 10 as soon as possible.