The Fab Four legend took to social media on Saturday (25Feb17) to mark the occasion with an old snap of the pair during a recording session.

"My lovely friend George," the 74-year-old posted on Twitter. "Still celebrating his birthday. Lucky to have had him in my life."

George was born on 25 February, 1943, and met Paul at the age of 14. He went on to play lead guitar for The Beatles, alongside fellow band members Paul, John Lennon and Ringo Starr.

He died after a battle with lung cancer in November, 2001, at the age of 58.

Paul released a sweet statement following his close pal's death, writing: "He was a lovely guy and a very brave man and had a wonderful sense of humour. He is really just my baby brother."

Paul and Ringo, the last two surviving members of The Beatles, recently teamed up for a collaboration for the drummer's upcoming album.

The two stars shared photos of the get-together on Twitter, with Ringo captioning his post, "Thanks for coming over man and playing Great bass. I love you man peace and love (sic)."