The Princess of Wales joined the Prince of Wales to welcome the Emir of Qatar and his first wife, Sheikha Jawaher, on Tuesday to kick off the state visit.
It marked Kate's latest major appearance amid her gradual return to royal duties following cancer treatment.
For the special occasion, the Princess looked elegant dressed in a maroon coat dress crafted by Sarah Burton for Alexander McQueen. She spruced up her look with a matching hat by Sahar Millinery. Kate's brunette locks were styled in an elegant chignon, and she accessorised with pearl drop earrings and a pearl necklace which belonged to the late Queen Elizabeth.
Take a look at their arrival in the video below...
Her decision to wear maroon paid homage to the country's flag which featues maroon and a serrated band of white. Pearls, meanwhile, are closely associated with the country.
Echoing Kate's smart look, Prince William donned a crisp white shirt, a red patterned tie and a dark, longline coat.
While the Queen was due to be present at the arrival ceremony, she pulled out of the occasion on Monday evening due to lingering side effects from an earlier chest infection. Doctors have urged Camilla, 77, to take time to rest and recover fully. She contracted the illness a month ago following her long-haul trip to Australia and Samoa.
HELLO! understands that Her Majesty will attend the arrival lunch at Buckingham Palace, before joining their guests Sheikh Tamim and Sheikha Jawaher at the palace's picture gallery.
While Kate will be involved in the daytime elements of the state visit, she will not be present for the glittering state banquet at Buckingham Palace on Tuesday evening.
The Princess is preparing to host her annual Christmas carol service at Westminster Abbey on Friday 6 December, which aims to provide a moment of reflection about the importance of loved ones, especially during difficult times.
Keep scrolling for all the best photos from the first day of the state visit...
1/17
© Getty ImagesBraving the autumn chill
Sheikh Tamim bin Hamad Al Thani and the first of his three wives, Sheikha Jawaher, appeared in good spirits as they stepped off a plane this morning on day one of their state visit.
2/17
© Getty ImagesA colourful affair
Flags of Qatar and Union Jacks lined the Mall leading to Buckingham Palace.
3/17
© Getty ImagesPrincess Anne arrives
The monarch's sister Princess Anne was photographed arriving for the state visit.
4/17
© Getty ImagesKate and William greet the couple
Princess Kate and Prince William welcomed the couple earlier in the morning.
5/17
© Getty ImagesSheikha Jawaher oozed elegance in a mauve button-down coat which she paired with dazzling drop earrings. She wore her brunette tresses in pristine waves and rounded off her look with a slick of plum lipstick.
6/17
© James WhatlingBeaming King Charles
King Charles was all smiles as he prepared to welcome the Emir at Horse Guards Parade. He wore a white shirt, a smart coat, navy trousers and a coordinating blue tie.
7/17
© James WhatlingA touching moment
In one sweet moment, Prince William was spotted sweetly placing a supportive hand on his wife's shoulder.
8/17
© GettyA warm welcome
The royal mother-of-three made a series of presentations.
9/17
© WPA PoolKate's curtsy
During the state visit, Kate looked perfectly poised as she curtsied to her father-in-law. She quickly placed one leg behind the other and bobbed down into an elegant curtsy.
Historically, both males and females have bowed and curtsied at all times when greeting people who are of higher royal rank than they are, including family members. The gesture is often very subtle, and used as a sign of respect for the royal family.
Take a look at Kate's curtsy in the video below...
10/17
© Getty ImagesInspecting the Guard
His Majesty then introduced his guests to a line up of dignitaries, inclding Prime Minster Sir Keir Starmer, foreign secretary David Lammy, and home secretary Yvette Cooper.
A Guard of Honour, found by 1st Battalion Welsh guards then gave a Royal Salute and the Qatari National Anthem was played by the band of the Welsh Guards.
11/17
© James WhatlingKate's fashion
Kate wowed in an elegant burgundy coat dress complete with structured shoulders, double-breasted detailing and a figure-flattering cut.
A matching burgundy beret by Sahar Millinery elevated her look.
As for accessories, Kate glittered in the late Queen Elizabeth II's precious pearls, which she first wore at Prince Phillip's funeral, then again at Her Majesty's funeral in 2022; a sign the former monarch had left her the sentimental jewels.
12/17
© GettyQueen Camilla
Despite pulling out of the open-air event, Camilla appeared in high spirits as she rode in the back of a car.
13/17
© Getty ImagesCarriage procession
Following the formalities, the Master of the Horse Lord Ashton of Hyde escorted the Emir and Sheikha to the Irish State Coach to join the King for the procession back to the Palace.
14/17
© Getty ImagesWilliam and Kate followed in the Australian State Coach with Qatar's prime minister and minister for foreign affairs, Sheikh Mohammed bin Abdulrahman bin Jassim Al Thani.
Other dignitaries followed in a series of State Landaus for the journey down The Mall to the Palace.
At the Grand Entrance, they were greeted by another Guard of Honour, found from 1st Battalion Welsh Guards and the band of the Irish Guards, who played the Qatari and British National Anthems.
15/17
© Getty ImagesPicture gallery
Discussing the collection on show, specifically chosen by curators at the RCT, King told the Emir: "It's the most absolutely extraordinary library you've ever seen."
16/17
© GettySenior royals
The Prince and Princess walked together as they toured the artefacts, stopping to discuss the works documenting the origins of Qatar as far back as the Roman Empire.
They included two books specially chosen by the RCT including a copy of Pliny the Elder's Natural History from 1481 and Ptolemy's Cosmography showing the city of Cotara on the first known map of the Arabian Peninsula from 1482.
William IV acquired these rare editions for the Royal Library in the 1830s.
The Emir also seemed fascinated by the book Victory over Abu Derya, which was written and illustrated by the cultural heritage expert Mohammed Ali.
17/17
© GettySignificant items
The story of pearl diving in Qatari seas was presented to Queen Elizabeth Il and Sheikha Mozah Bint Nasser Al Missned at the launch of Bloomsbury Qatar Foundation Publishing in April 2010.
The publishing venture was among the cultural partnerships noted in Queen Elizabeth Il's speech during the State Visit of Sheikh Hamad bin Khalifa Al Thani and Sheikha Mozah to the UK in October 2010.
When the late Queen had visited Qatar in 1979 - the first British Sovereign to do so - the National Museum had presented the sovereign with a silver model of another traditional boat, the dhow, a national symbol included in the coat of arms of Qatar, also on display in the gallery.
