Mick Jagger and Keith Richards honored their one-time collaborator and longtime friend Marianne Faithfull following her death on Thursday. Faithfull died on Jan. 30 at age 78, a spokesperson previously confirmed to PEOPLE.

Rolling Stones frontman Mick Jagger, who enjoyed a romantic relationship with Faithfull in the 1960s, also paid tribute. Writing on X, he said, "I am so saddened to hear of the death of Marianne Faithfull. She was so much part of my life for so long. She was a wonderful friend, a beautiful singer and a great actress. She will always be remembered."