Jamie Cullum wasn't "mature enough to understand" his late friend Amy Winehouse's battle with addiction.
The 39-year-old musician was close friends with the 'Back To Black' singer before she tragically passed away from alcohol poisoning in 2011 at the age of 27, and he's now said he doesn't think he fully understood the seriousness of her battle with addiction.
He said: "I don't think I was really mature enough to understand what was happening to her at that point, the true levels of her addiction."
But the 'Don't Stop the Music' musician - who is now married to Sophie Dahl - did say the late singer was exactly his "type of person", and the two of them would often just listen to music together.
He added: "She was the kind of person, it reminded me of myself, where if the night wasn't good, who would be like, 'let's go back to someone's house and listen to records' and she was that kind of person and I was like, 'that's totally my type of person'."
Jamie drew inspiration for his latest song 'The Age of Anxiety' from his friendship with Amy, after stumbling across an old text message chain he'd had with the 'Valarie' singer in the early 2000s.
Speaking to BBC Radio 5 Live presenter, Nihal Arthanayake, he said: "I thought I'd just look inwardly and think about the things that make me feel anxious and just generally confused.
"One of the things that happened in the last couple of years whilst I was writing, I was clearing out my own studio and I found an old Blackberry, I plugged it in and found all my old text messages between me and Amy Winehouse.
"We toured together and we were friends in the early 2000s, for a good kind of four to five years before 'Back To Black' ... just reading them text messages and seeing how it was at one time and watching it unfold just broke my heart ... It was just so unbelievably sad.
"I can safely say I knew she was a genius, no question, I knew her as the music nerd type who just used to always talk about Ray Charles and Natkin Cole and Frank Sinatra."
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