Separately, Mr Slack, who has since become deputy editor of The Sun newspaper, released an apology for his involvement in the events.
“I wish to apologise unreservedly for the anger and hurt caused,” he said. “This event should not have happened at the time that it did. I am deeply sorry, and take full responsibility.”
Downing Street also faced internal criticism from civil servants who felt No 10 had let down other government departments that had followed both the coronavirus regulations and the guidelines for the official period of mourning that followed the Duke’s death on Apr 9 last year.
The guidance stated that ministers attending public-facing events should wear a “dark coat, suit, or day dress”, as well as dark gloves and hats if needed.
Flags hung at half mast in Whitehall, while all government announcements during the mourning period required the express permission of Downing Street.
‘Clowns’ in No 10 made mockery of rules
One civil service source told The Telegraph that “clowns” in No 10 had made a mockery of the rules by hosting the leaving parties.
“It came around pretty quickly from No 10 – basically a pause on everything,” the source said. “Stories and announcements planned for months were understandably paused.
“People get that, but they’re annoyed that they were all acting diligently whilst these clowns were doing this.”
Another source said that some No 10 staff had objected to the organising of a leaving party for Mr Slack because they were concerned it would constitute a breach of the Covid regulations.
A source said: “Some of us told a senior colleague in private office that anything marking James’ leaving needed to wait until we were out of the roadmap; that even though he was a wonderful colleague and long-standing member of No 10, it was hard to justify and simply didn’t look good.”
It was also claimed on Friday that Mr Johnson encouraged regular “wine time Fridays” in Downing Street during the pandemic to help staff “let off steam”. The Daily Mirror reported that staff used a suitcase to stock up on wine and beer from a local shop, and kept the drinks cool in a fridge in the office.
The revelations in the Telegraph piled pressure on Scotland Yard to open a formal criminal probe into rule-breaking by No10 staff.
