Adam Lambert arrives for the Together At Christmas concert at Westminster Abbey in London on Dec. 8; Kate Middleton at Together At Christmas on Dec. 8.Photo:getty (2)

Adam Lambert and Kate Middleton

getty (2)

Lambert, 41, was among the artists tapped to perform at the Princess of Wales’ third annual Christmas carol service, which was held at Westminster Abbey last Friday. TheAmerican Idolalum exclusively tells PEOPLE that it was surreal to sing inside the historic abbey — and shared that he connected with Princess Kate ahead of his performance.

“I had the honor of meeting Catherine, Princess of Wales. She invited the performers she wanted to see at the service, and it was lovely to visit with her before we performed,” Lambert tells PEOPLE.

Lambert sang “The Christmas Song” alongside British singer-songwriter Beverley Knight shortly beforePrince Williamdelivered a Bible reading. An attendee said that George, Charlotte and Louis “watched intently” as Lambert and Knight sang the Christmas classic.

According to the artist, the atmosphere inside Westminster Abbey (where the Prince and Princess of Wales wed in 2011 andKing Charleswas crowned in May) was completely serene when it came time to hit the mic.

Kate Middleton chats with Adam Lambert at the Together At Christmas concert at Westminster Abbey in London on Dec. 8.Chris Jackson/Getty

DECEMBER 08: Catherine, Princess of Wales speaks with Adam Lambert at The “Together At Christmas” Carol Service at Westminster Abbey on December 08, 2023 in London, England. Spearheaded by The Princess of Wales, and supported by The Royal Foundation, the service is a moment to bring people together at Christmas time and recognise those who have gone above and beyond to help others throughout the year.

Chris Jackson/Getty

The “Whataya Want from Me” hitmaker, who first rose to fame on season 8 ofAmerican Idol, says that the depth of the setting added to the grandeur.

“I’ve always loved history and old architecture, and this is sort of my sweet spot. I was able to walk around a little bit after my rehearsal and just kind of take a little self-guided tour of some of the areas inside at the Abbey and it’s just breathtaking, and the amount of history in here is nuts,” Lambert says. “You know you have the tombs of monarchs and poets and other iconic historical figures, so it’s pretty wild.”

“It’s such an honor to be performing at the Westminster Abbey, a place that I’ve seen on television and in photos for years but have never been to myself, so it is quite breathtaking."

He was also “excited” to meet the royal family in the intimate setting.

“I’ve performed for the royals during the Queen’s Jubilee but they were quite far away on the other side of the crowd," he says. “So this will be sort of up close and personal and hopefully bringing Christmas cheer to people that tune in on Christmas Eve.”

In June 2022, the star performed at the BBC’s “Platinum Party at the Palace” concert celebratingQueen Elizabeth’s Platinum Jubilee through theQueen+ Adam Lambert collaboration. The musical partnership between the American singer and members of the iconic British rock band opened the show epically held outside Buckingham Palace during the weekend of festivities marking Queen Elizabeth’s record 70-year reign.

Adam Lambert performs during the Platinum Party at the Palace in June 2022.Yui Mok/PA Images via Getty

Adam Lambert performs during the Platinum Party at the Palace staged in front of Buckingham Palace, London, on day three of the Platinum Jubilee celebrations for Queen Elizabeth II. Picture date: Saturday June 4, 2022.

Yui Mok/PA Images via Getty

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The latest carol service was linked to The Royal Foundation for Early Childhood’s Shaping Us campaign that Princess Kate launched in January to raise awareness around the early years, and Kensington Palace said that the Dec. 24 broadcast will feature additional content around the topic.

Adam Lambert arrives for the Together At Christmas concert at Westminster Abbey in London on Dec. 8.Samir Hussein/WireImage

LONDON, ENGLAND - DECEMBER 08: Adam Lambert attends The “Together At Christmas” Carol Service at Westminster Abbey on December 08, 2023 in London, England

Samir Hussein/WireImage

PEOPLE’s new special edition,Christmas at the Palace: A Royal Family Album, is available now on Amazon and wherever magazines are sold.

“It’s a really flattering invite to receive from Princess Kate, to come and sing at this special event,” Lambert told PEOPLE, adding that he hoped she enjoyed what they had “in store for her.”

source: people.com