Among the most poignant of ceremonies before the Queen’s state funeral will be the vigil of princes on Friday evening, when the King and his siblings will stand watch over her coffin during her official lying in state.
The King, the Princess Royal, the Duke of York and the Earl of Wessex will mount guard at the four corners of the catafalque in Westminster Hall for the 15-minute vigil. All will be in military uniform, including Prince Andrew, who as a non-working royal has been granted dispensation to wear uniform for this most personal of gestures.
The King is “focused on leading the family, the nation, the realms and the Commonwealth in mourning for Queen Elizabeth II”, his spokesperson said.
Charles is due to host his first large state event at Buckingham Palace in the form of an official reception for heads of state, foreign royals and overseas official visitors before the state funeral.
It follows a busy few days of engagements, when he travelled to Edinburgh and Belfast.
He is scheduled to meet the military chiefs of staff at Buckingham Palace on Saturday, and to attend a lunch for governors general with the Queen Consort, and will then meet realm prime ministers at Buckingham Palace.
On Friday, Charles, who was the longest-serving Prince of Wales in UK history, will return to Wales as King, when he and the Queen Consort travel to Cardiff and receive a message of condolence from the Welsh Senedd.
He will hold a private audience with the Welsh first minister, Mark Drakeford, at Cardiff Castle before attending a reception in the banqueting hall hosted by the Welsh government.
His arrival by helicopter in Wales will be marked with a 21-gun salute. King Charles and Camilla will also travel to Llandaff Cathedral for a service of prayer and reflection.
On his return to Buckingham Palace, Charles will host faith leaders in the Bow Room at Buckingham Palace before travelling to Westminster Hall to mount the vigil with his siblings.
He was spending Thursday at Highgrove, Gloucestershire, where he was said to be undertaking state business, receiving his red boxes, and receiving calls from governors general and heads of state.