King Charles' staff were told they could lose their jobs during a church service for the Queen.
Dozens of employees are said to be livid with up to 100 Clarence House workers facing redundancy, according to reports.
Staff members were reportedly given notice as King Charles and Camilla Queen Consort prepare to move to Buckingham Palace following the death of the Queen.
It is understood that up to 100 workers could be affected by the switch up as the King changes his official residence, reports the Guardian.
Staff supporting the former Prince of Wales have been working round the clock to smooth his rise to the throne.
Those believed to be impacted by the redundancy notice are said to be private secretaries, the finance office, the communications team and household staff.
They discovered their posts were on the line during the thanksgiving service for the Queen at St Giles' Cathedral in Edinburgh on Monday.
Some staff allegedly assumed they would receive new roles at the King's new household.
But sources said they had no indication what was coming until they received a letter from Sir Clive Alderton, the King's top aide.
The letter, seen by the Guardian, read: "The change in role for our principals will also mean change for our household…
"The portfolio of work previously undertaken in this household supporting the former Prince of Wales’s personal interests, former activities and household operations will no longer be carried out, and the household … at Clarence House will be closed down.
"It is therefore expected that the need for the posts principally based at Clarence House, whose work supports these areas will no longer be needed."
Sir Alderton continued in the letter: "I appreciate that this is unsettling news and I wanted to let you know of the support that is available at this point."
One source said "everybody is absolutely livid" including private secretaries and the senior team.
"All the staff have been working late every night since Thursday, to be met with this. People were visibly shaken by it," they added.
Sir Alderton further explained that some staff who give "direct, close, personal support and advice" to Charles and Camilla would stay within their role.
It is understood no final decisions have been made, with a consultation period having to be completed first after the Queen's funeral on Monday.
Staff who are made redundant could allegedly be offered alternative work at other royal households and an "enhanced" redundancy payment beyond the statutory minimum.
A Clarence House spokesman said: “Following last week’s accession, the operations of the household of the former Prince of Wales and Duchess of Cornwall have ceased and, as required by law, a consultation process has begun.
"Our staff have given long and loyal service and, while some redundancies will be unavoidable, we are working urgently to identify alternative roles for the greatest number of staff.”
