The King will be anointed at his coronation in full knowledge of his “difficult” task as monarch and in recognition of how he “shares in our human frailties and vulnerabilities”, the Archbishop of Canterbury has said.

Archbishop Justin Welby, writing in the official coronation souvenir programme, said Charles will swap his “robes of status and honour” for a simple white shirt for the private anointing during the May 6 ceremony.

He wrote of how the historic occasion will be one of “magnificence and pomp” but also in the midst of the ceremony one of “stillness and simplicity” when the King is anointed with holy oil in private under a canopy – in what forms the most sacred part of the coronation.

The the front cover of the official souvenir programme celebrating the coronation of King Charles III and the Queen Consort (Publications UK Ltd/PA)

The 84-page official souvenir, which costs £20, went on sale on Monday, and features a full page photo of the Duke and Duchess of Sussex with Charles, Camilla, the now-Prince and Princess of Wales and the Waleses’ children.

Harry, who is attending the ceremony, and Meghan, who is not, are pictured in a previously seen portrait taken to mark Charles’s 70th birthday in 2018.

The duke is to appear alongside his family in public at the coronation for the first time since he lambasted Charles, Camilla, William and Kate in his autobiography Spare.

With just over two weeks to go until the May 6 ceremony, it was revealed that the King and Queen Consort have personally chosen Coronation Quiche as their celebratory recipe.

Seventy years after Coronation Chicken was created for Elizabeth II’s coronation, Charles and Camilla selected a personal favourite as their recommended dish for Coronation Big Lunches.

The recipe is by royal head chef Mark Flanagan and features spinach, broad beans and tarragon.

A Coronation Quiche is the dish chosen by the King and the Queen Consort (Buckingham Palace/PA)

Further details also emerged about the celebrations, with the eve of the coronation set to be marked by a glittering Buckingham Palace reception attended by foreign royalty.

Princess Beatrix, the former queen of the Netherlands, has confirmed her attendance at the event, expected to be hosted by Charles, alongside her granddaughter and heir to the Dutch throne Catharina-Amalia, the Princess of Orange.

King Willem-Alexander and Queen Maxima of the Netherlands will not be among the guests, who are likely to include British royalty and presidents and prime ministers from across the globe, but will be at Westminster Abbey to see Charles and Camilla crowned.

The King’s anointing is the only part of the ceremony the public will not see and will be a “private moment between a new King and the King of Kings”, the Archbishop said.

Elizabeth II was also anointed in private as is the tradition, wearing a plain pleated linen dress over her coronation gown, as she sat beneath a golden canopy.

The Archbishop said, the King, dressed in the simple white garment, will come before God as a servant “in the full knowledge that the task is difficult and he needs help”.

He added: “In the full knowledge that even as a King, he is one of the people and that even if he has a particular role to fulfil, he shares in our human frailties and vulnerabilities”.

The service will move to the moment of crowning as the mood turns to one of celebration, he added.

The Archbishop described how coronations “often carry with them the hopes and prayers of nations for peace, justice and the common good”.

A percentage of the sales of the souvenir programme will be split between two charities – the Royal Collection Trust and SSAFA, the Armed Forces charity.