The King held a meeting with Governor of Victoria Linda Dessau at the royal residence on Wednesday morning, where he has been spending time following the end of the official royal mourning period.
WATCH: Royals return to official duties as mourning period ends
Photos released from the meeting showed the pair standing in the library, and eagle-eyed fans noticed that although much of the room has remained untouched since the Queen's death, King Charles has made a couple of updates to add his own personal touches into the room.
They include swapping out two green armchairs for bold red leather chairs topped with colourful patchwork cushions, creating a comfortable spot for meetings or to relax.
King Charles appears to have updated the decor in Balmoral's library
Another new addition to the space appeared to be a thermostat positioned on the mantelpiece of the room alongside a pair of running figurine lamps and an antique clock that was said to have been treasured by the Queen.
Charles had also removed an electric heater that had previously been seen in front of the open fireplace, however, it may not have been cold enough to need a heater on during Wednesday's meeting.
The Queen held a meeting in the room in 2017
While Charles had made a couple of small updates to the room, photos dating back as far as 1977 reveal that it has hardly changed in that time, with the same book-lined shelves, antique side table and decorative items that have been there for 45 years.
Much of the room has remained the same for 45 years
The King and Queen Consort are enjoying some time at Balmoral but are expected to return to London this month. The couple are continuing to live at their home of almost 20 years, Clarence House, following Charles' accession to the throne, but are reportedly moving into Buckingham Palace sooner than expected in spring 2023, when reservicing works are partially completed.
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