The Princess of Wales will make a joint appearance with the Prince of Wales next week, amid her gradual return to royal duties.
Kate, 42, who is recovering from cancer, will join Prince William, 42, in greeting Sheikh Tamim bin Hamad Al Thani and the first of his three wives, Sheikha Jawaher bint Hamad bin Suhaim Al Thani, at Kensington Palace on 3 December as part of the Emir of Qatar's state visit to the UK.
The Prince and Princess will take part in the carriage procession to Horse Guards Parade where the Emir will receive a ceremonial welcome before meeting the King and Queen.
While Kate will be involved in the daytime elements of the visit, she will not attend the state banquet at Buckingham Palace on Tuesday evening.
This means that royal fans are unlikely to see the Princess wearing a tiara this year, as state banquets are usually one of the very few white-tie events the royals attend.
Kate was also absent from this year's diplomatic reception, which was held at Buckingham Palace last week. William made a solo appearance at the soiree alongside Charles and Camilla.
The Queen wore a blue velvet evening gown by Fiona Clare and made her debut in the late Queen Elizabeth II's small aquamarine and diamond tiara.
Tiaras are typically reserved for state banquets, the annual diplomatic reception and royal weddings but in eras gone by, the likes of the Queen Mother, then Princess Elizabeth and Princess Margaret would wear the jewels for film premieres and galas.
Since marrying William in 2011, Kate has worn four tiaras from the royal family's jewellery collection – the Cartier Halo, the Lotus Flower, the Lover's Knot and the Strathmore Rose tiaras.
Kate's return to royal duties
The Princess has made just a handful of public appearances so far in 2024, after she underwent major abdominal surgery in January and then was diagnosed with cancer.
Last month, Kate made a surprise visit with William to meet the bereaved families of the victims of the Southport attack.
She also stepped out for Remembrance events in London earlier this month.
On 6 December, the Princess will host her annual Christmas carol service at Westminster Abbey.
While the royals traditionally spend the festive service at Sandringham, turning out to attend church on Christmas Day, Kensington Palace is yet to confirm William and Kate's plans this year.
The couple have only missed Christmas with the royal family on two occasions – in 2012, when Kate was suffering with hyperemesis gravidarum during her first pregnancy with Prince George, and in 2016, they spent the day with the Middletons.