Ms Josephs, who was awarded the Companion of the Order of the Bath in the Queen’s Birthday honours last June in recognition of her exemplary public service, left the Government the following day.
After being approached by this newspaper, Ms Josephs said she was “truly sorry that I did this and for the anger that people will feel as a result”.
Confirming she was “co-operating fully” with the investigation, she said: “On the evening of 17 December, I gathered with colleagues that were at work that day, with drinks, in our office in the Cabinet Office, to mark my leaving the Civil Service.
“Sheffield has suffered greatly during this pandemic, and I apologise unreservedly. The specific facts of this event will be considered in the context of the Cabinet Office investigation. I did not attend any events at 10 Downing Street.
“I will not be able to respond to any further questions until the Cabinet Office investigation is complete.”
Meanwhile, Terry Fox, the leader of Sheffield City Council, expressed his “deep disappointment” in response, adding: “People will rightly feel angry and let down. I get that completely.”