Brad Pitt and Angelina Jolie have a cup of tea with Prince William and Kate

The Duke and Duchess of Cambridge (née Kate Middleton) received some special visitors at Kensington Palace on Friday (June 26) when Brad Pitt and Angelina Joliestopped by the royal homestead for tea - and stayed longer than planned.

"The Duke and Duchess of Cambridge met with Brad Pitt and Angelina Jolie Pitt at Kensington Palace on Friday afternoon," a Kensington Palace spokesperson told HELLO! magazine. "They discussed their shared interest in combatting the illegal wildlife trade."

Another source revealed to Us Weekly that the Cambridges were "really excited" to welcome the Hollywood couple met, and even greeted Brad and Angelina outside their palatial home, Apartment 1A.

The Cambridges and the Jolie-Pitts share a passion for wildlife preservation. Photo: © Getty Images

This was reportedly the first meeting of the two high-profile couples, and the Jolie-PItts - who are in town for a Monday lunch at the Foreign & Commonwealth Office - came bearing a gift to celebrate Princess Charlotte's arrival.

Read More: The cutest photos of Prince William with George and Charlotte

Prince William has been a longtime supporter of wildlife causes and in 2014 he launched the charitable initiative United for Wildlife through The Royal Foundation of the Duke and Duchess of Cambridge and Prince Harry. It has yet to be confirmed if Brad and Angelina will be lending their voice to the project that already sees tennis ace Andy Murray and David Beckham as devoted ambassadors, but given the actors' dedication to social issues it is likely that they might have offered the Duke their support.

Prince William and Kate were thrilled to host Brad and Angelina. Photo: © Getty Images

The last time the 40-year-old actress mingled with the royal family was back in October 2014, when she met with the Queen at Buckingham Palace to receive an honorary damehood. During an intimate one-on-one audience with Her Majesty , Angelina, who is a special envoy to the UNHCR, was presented with the prestigious Insignia of an Honorary Dame Grand Cross of the Most Distinguished Order of St. Michael and St. George for her services to end warzone sexual violence.

“To receive an honour related to foreign policy means a great deal to me, as it is what I wish to dedicate my working life to ,” said Angelina. “Working on the Preventing Sexual Violence Initiative and with survivors of rape is an honour in itself. I know that succeeding in our goals will take a lifetime, and I am dedicated to it for all of mine.”

Angelina Jolie was made an Honourary Dame by the Queen. Photo: © PA

With the get together an adults-only affair, the couples will have to plan another date so that their children, including Prince George and Princess Charlotte, will have a chance to meet the Hollywood power couple's six children.

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