King Charles III's staff were reportedly given redundancy notices after they worked around the clock to help smooth the King's accession to the throne following Queen Elizabeth II's death.
According to the Guardian, dozens of staff members at the King's former official residence, Clarence House, were told during the thanksgiving service for the Queen in Edinburgh on Monday (local time).
In a letter from the King's top aide Sir Clive Alderton, which the Guardian has seen, it said the role change for the former Prince of Wales and Duchess of Cornwall meant Clarence House would be "closed down".
The news outlet shared up to 100 employees are at risk of losing their jobs with private secretaries, the finance office, the communications team and household staff positions on the line.
"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," the letter said.
Staff who are made redundant are expected to be offered help finding alternative employment across all royal households and offered an "enhanced" redundancy package.
It is understood that no staff will be affected for at least three months.
Staff told the outlet they were "livid" by the decision and that they had been working later every night since the Queen died.
The Public and Commercial Services Union (PCS) condemned the decision to announce redundancies during the period of morning, telling the BBC it was "nothing short of heartless".
The mourning period for the Queen goes for 10 days and ends on September 19.