LONDON (Reuters) - Britain's Prince William posed for a photo with U.S. music star Taylor Swift and two of his children, Charlotte and George, at the first night of Swift's Eras tour in London on Friday.

A photo posted on Kensington Palace's X social media feed with the caption "Thank you @taylorswift13 for a great evening!" showed William smiling as Swift took a selfie with him and the children. William celebrated his 42nd birthday on Friday.

Swift also posted a different photo of her with the royals and her partner Travis Kelce with the message: "Happy Bday M8! London shows are off to a splendid start".

Ahead of the first of her eight shows at London's Wembley Stadium, the city published a special version of its distinctive London Underground map to mark the occasion, and the "Changing of the Guard" ceremony at Buckingham Palace featured a military band rendition of one of her songs.

(Reporting by William James; Editing by Mark Potter)